Equity Components [Axis] Common Stock [Member] Stock Subscription Receivable [Member] Additional Paid-in Capital [Member] Statutory Reserve [Member] AOCI Attributable to Parent [Member] Retained Earnings [Member] Parent [Member] Noncontrolling Interest [Member] Investment, Name [Axis] Jiangshan BVI [Member] HK Changfeng [Member] Liyun Holding Limited [Member] Hong Kong Qinan Holding Limited [Member] Business Combination [Axis] Julong Online (Beijing) Technology Development Co., Ltd. [Member] Related and Nonrelated Parties [Axis] Shareholder [Member] Beijing Junxinyuan Technology Development Co. Ltd. [Member] Datongyi Holding Limited Member] Qiren Holding Limited [Member] Product and Service [Axis] Engineering Solution Service [Member] System Maintenance Revenue [Member] Concentration Risk Benchmark [Axis] Revenue Benchmark [Member] Concentration Risk Type [Axis] Customer Concentration Risk [Member] Customer [Axis] Customer A [Member] Customer B [Member] Customer C [Member] Accounts Receivable [Member] Customer D [Member] Total Purchases [Member] Supplier Concentration Risk [Member] Supplier A [Member] Supplier B [Member] Supplier C [Member] Long-Lived Tangible Asset [Axis] Motor vehicles [Member] Electronic devices, furniture and office equipment [Member] Software Development [Member] Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Loan Facility Agreement [Member] Engineering Solutions of Intelligent Projects [Member] Operation and Maintenance of Intelligent Projects [Member] Sales of Equipment and Materials of Intelligent Systems [Member] Timing of Transfer of Good or Service [Axis] Transferred at Point in Time [Member] Transferred over Time [Member] Award Type [Axis] Two-Tiered Profit Two [Member] Geographical [Axis] HONG KONG Two-Tiered Profit One [Member] Income Tax Jurisdiction [Axis] CHINA Statistical Measurement [Axis] Minimum [Member] Legal Entity [Axis] High And New Technology Enterprises [Member] Beijing Yihai Construction Engineering Co., Ltd. [Member] Beijing Jianlei International Decoration Engineering Co., Ltd. [Member] Wu Yue [Member] Service [Member] Beijing Huiju Tianxia Investment Co., Ltd [Member] Subsequent Event Type [Axis] Subsequent Event [Member] Sale of Stock [Axis] IPO [Member] Over-Allotment Option [Member] Class of Stock [Axis] Common Class A [Member] Cover [Abstract] Document Type Amendment Flag Amendment Description Document Registration Statement Document Annual Report Document Quarterly Report Document Transition Report Document Shell Company Report Document Shell Company Event Date Document Period Start Date Document Period End Date Document Fiscal Period Focus Document Fiscal Year Focus Current Fiscal Year End Date Entity File Number Entity Registrant Name Entity Central Index Key Entity Primary SIC Number Entity Tax Identification Number Entity Incorporation, State or Country Code Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Three Entity Address, City or Town Entity Address, State or Province Entity Address, Country Entity Address, Postal Zip Code Country Region City Area Code Local Phone Number Extension Written Communications Soliciting Material Pre-commencement Tender Offer Pre-commencement Issuer Tender Offer Title of 12(b) Security No Trading Symbol Flag Trading Symbol Security Exchange Name Title of 12(g) Security Security Reporting Obligation Annual Information Form Audited Annual Financial Statements Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Interactive Data Current Entity Filer Category Entity Small Business Entity Emerging Growth Company Elected Not To Use the Extended Transition Period Document Accounting Standard Other Reporting Standard Item Number Entity Shell Company Entity Public Float Entity Bankruptcy Proceedings, Reporting Current Entity Common Stock, Shares Outstanding Documents Incorporated by Reference [Text Block] Statement of Financial Position [Abstract] ASSETS Current assets Cash and cash equivalents Restricted cash Accounts receivable (net of allowance of RMB641,101 and RMB738,023 as of September 30,2024 and March 31, 2025, respectively) Other receivable (net of allowance of RMB2,630 and nil as of September 30, 2024 and March 31, 2025, respectively) Amounts due from related parties Contract assets-current (net of allowance of RMB2,292,498 and RMB2,604,481 as of September 30, 2024 and March 31, 2025, respectively) Prepaid expenses and other current assets Total current assets Non-current assets Property, plant and equipment, net Deferred tax assets Operating lease right-of-use assets Contract assets- non-current, net Total non-current assets TOTAL ASSETS LIABILITIES Current liabilities Short-term borrowing Accounts payable Contract liabilities Accrued expenses and other current liabilities Amounts due to related parties Income tax payable Operating lease liabilities, current portion Total current liabilities Non-current liabilities Total non-current liabilities TOTAL LIABILITIES SHAREHOLDERS’ EQUITY Stock Subscription Receivable Ordinary shares subscribed (US$0.0001 par value, 500,000,000 shares authorized as of September 30, 2024 and March 31, 2025; 20,011,132 shares issued and outstanding as of September 30, 2024 and March 31, 20251) Statutory reserve Retained earnings TOTAL SHAREHOLDERS’ EQUITY TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY Accounts receivable, allowance Other receivable, allowance Contract assets-current, allowance Ordinary shares, par value Ordinary shares, shares authorized Ordinary shares, shares issued Ordinary shares, shares outstanding Income Statement [Abstract] Revenues Cost of revenues Gross profit Operating expenses: Selling, general and administrative expenses Total operating expenses Operating income Interest (expense) income, net Other income, net Income before income taxes Income tax expenses Net income Other comprehensive income, net of tax of nil: Comprehensive income Other comprehensive income, tax Statement [Table] Statement [Line Items] Balance Balance, shares Net income for the year Provision of statutory reserve Reorganization in February 2024 Foreign currency translation adjustment Balance Balance, shares Statement of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES Net income Adjustments to reconcile net income to net cash provided by (used in) operating activities: Depreciation of property, plant and equipment Amortization of the right-of-use assets Provision of allowance for doubtful accounts Provision of allowance for contract assets Changes in operating assets and liabilities Accounts receivable Other receivable Prepaid expenses and other current assets Contract assets Amount due from related parties Deferred tax assets Non-current assets Accounts payable Accrued expenses and other current liabilities Income tax payable Contract liabilities Amount due to related parties Lease liabilities Other Current liabilities Net cash provided by (used in) operating activities CASH FLOWS FROM INVESTING ACTIVITIES Acquisition of Julong Online Net cash (used in) investing activities CASH FLOWS FROM FINANCING ACTIVITIES Repayment of short-term borrowing Payment of deferred offering costs Net cash (used in) provided by financing activities Net (decrease) increase in cash, cash equivalents and restricted cash Cash, cash equivalents and restricted cash at beginning of the period Cash, cash equivalents and restricted cash at end of the period Supplemental disclosure of cash flow information - Income taxes (refund) - Interest paid Accounting Policies [Abstract] ORGANIZATION AND PRINCIPAL ACTIVITIES SIGNIFICANT ACCOUNTING POLICIES Recent Accounting Pronouncements Recent accounting pronouncements Risks and Uncertainties [Abstract] Concentration and risks Credit Loss [Abstract] ACCOUNTS RECEIVABLE, NET Contract Assets And Contract Liabilities CONTRACT ASSETS AND CONTRACT LIABILITIES Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] PREPAID EXPENSES AND OTHER CURRENT ASSETS Property, Plant and Equipment [Abstract] PROPERTY, PLANT AND EQUIPMENT, NET Debt Disclosure [Abstract] SHORT-TERM BORROWING Payables and Accruals [Abstract] ACCRUED EXPENSES AND OTHER CURRENT LIABILITIES Leases LEASES Fair Value Disclosures [Abstract] FAIR VALUE MEASUREMENT Revenue from Contract with Customer [Abstract] REVENUE Income Tax Disclosure [Abstract] INCOME TAXES Retirement Benefits [Abstract] EMPLOYEE BENEFITS Earnings Per Share [Abstract] NET INCOME PER SHARE Related Party Transactions [Abstract] RELATED PARTY TRANSACTION Commitments and Contingencies Disclosure [Abstract] COMMITMENTS AND CONTINGENCIES Segment Reporting [Abstract] SEGMENT INFORMATION Subsequent Events [Abstract] SUBSEQUENT EVENT Principles of presentation and consolidation Use of estimates Functional currency and foreign currency translation Convenience translation Fair value Cash, cash equivalents Restricted Cash Accounts receivable and allowance for doubtful accounts Contract Assets and Contract Liabilities Deferred Offering Costs Revenue recognition Taxation Leases Income per share Comprehensive income Schedule of concentration of credit risk SCHEDULE OF ACCOUNTS RECEIVABLE AND ALLOWANCE FOR DOUBTFUL ACCOUNTS SCHEDULE OF ALLOWANCE FOR DOUBTFUL ACCOUNTS RELATED TO ACCOUNTS RECEIVABLE SCHEDULE OF CONTRACT ASSETS AND CONTRACT LIABILITIES SCHEDULE OF MOVEMENTS IN THE ALLOWANCE FOR CREDIT LOSS RELATED TO CONTRACT ASSETS SCHEDULE OF PREPAID EXPENSES AND OTHER CURRENT ASSETS SCHEDULE OF PROPERTY, PLANT AND EQUIPMENT, NET SCHEDULE OF ACCRUED EXPENSES AND OTHER CURRENT LIABILITIES SCHEDULE OF COMPONENTS OF LEASE EXPENSES SCHEDULE OF SUPPLEMENTAL CASH FLOWS INFORMATION RELATED TO LEASES SCHEDULE OF SUPPLEMENTAL BALANCE SHEET INFORMATION RELATED TO LEASES SCHEDULE OF DISAGGREGATES OF REVENUE SCHEDULE OF REVENUES RECOGNIZED AT A POINT IN TIME OR OVER TIME SCHEDULE OF CURRENT AND DEFERRED COMPONENTS OF THE INCOME TAX EXPENSE SCHEDULE OF PRINCIPAL COMPONENTS OF DEFERRED TAX ASSETS AND DEFERRED TAX LIABILITIES SCHEDULE OF ROLL FORWARD OF VALUATION ALLOWANCES OF DEFERRED TAX ASSETS SCHEDULE OF RECONCILIATION OF INCOME TAX EXPENSE AT THE EFFECTIVE RATE FROM INCOME TAX SCHEDULE OF CALCULATING NET INCOME PER SHARE SCHEDULE OF MAJOR RELATED PARTIES AND THEIR RESPECTIVE RELATIONSHIP SCHEDULE OF RELATED PARTIES TRANSACTION Equity interest percentage Business combination, consideration transferred Business combination, voting equity interest acquired percentage Business combination, shares issued Nature of Operation, Product Information, Concentration of Risk [Table] Product Information [Line Items] Sale of Stock, Price Per Share Foreign currency exchange rate, translation Deferred offering costs Transaction price allocated to the performance obligations expected to recognize as revenue Uncertain tax positions Concentration Risk [Table] Concentration Risk [Line Items] Concentration of customers amount Concentration of customers amount Concentration of suppliers amount Cash and cash equivalents and time deposits Accounts receivable Less: allowance for doubtful accounts Total Accounts receivable, net Beginning of the year (Reversal) provision of allowance for doubtful accounts End of the year/period Schedule Of Contract Assets And Contract Liabilities Contract assets – current, net: Revenue recognized in excess of amounts paid or billed (account receivable) to the Group on uncompleted contracts Retention receivables Less: allowance for credit loss Total Contract assets – non- current, net: Retention receivables Less: allowance for credit loss Total Contract liabilities: Payments received or receivable in excess of revenue recognized on uncompleted contracts Total Schedule Of Movements In Allowance For Credit Loss Related To Contract Assets Balance at beginning of the year Additions Balance at end of the year/period Prepayment for inventories and others Prepaid taxes Total Property, Plant and Equipment [Table] Property, Plant and Equipment [Line Items] Total Less: accumulated depreciation Property, plant and equipment, net Depreciation expenses Collaborative Arrangement and Arrangement Other than Collaborative [Table] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Borrowing capacity Interest rate Maturity date description Salary and welfare payable Accrued liabilities to suppliers Other tax payable Supplier deposit for quality Service fee Others Total Schedule Of Components Of Lease Expenses Lease cost Operating lease cost Short term lease cost Total lease cost Schedule Of Supplemental Cash Flows Information Related To Leases Operating cash flows from operating leases Operating leases Operating lease right-of-use assets, net Total operating lease assets Operating lease liabilities, current Operating lease liabilities, non-current Total operating lease liabilities Weighted average remaining lease term- operating lease Weighted average discount rate- operating lease Variable lease cost Sublease income Disaggregation of Revenue [Table] Disaggregation of Revenue [Line Items] Total Revenue remaining performance obligations Current tax expense Deferred tax expense Total Net operating loss carry-forwards Operating lease liabilities Allowance for receivables Total deferred tax assets Less: valuation allowance Total deferred tax assets, net Total deferred tax liabilities Deferred tax assets, net Balance Addition of valuation allowance Balance Income before income taxes Income tax expense computed at statutory income tax rate Tax effect of preferential tax rate Permanent differences Effect of income tax rate difference in other jurisdictions Change in valuation allowance Effective Income Tax Rate Reconciliation [Table] Effective Income Tax Rate Reconciliation [Line Items] Profits tax rate Income tax rate Preferential tax rate Employee benefit expenses Net income attributable to ordinary shareholders of Julong Holding Limited Weighted average number of ordinary shares outstanding - basic Weighted average number of ordinary shares outstanding - diluted Basic - net income per share Diluted - net income per share Related Party Transaction [Table] Related Party Transaction [Line Items] Relationship with the Company Total Amounts due from related parties Subsequent Event [Table] Subsequent Event [Line Items] Number of shares, additional Shares issued, price per share Net proceeds Gross proceeds Stock Subscription Receivable [Member] Statutory Reserve [Member] Hong Kong Qinan Holding Limited [Member] Provision of statutory reserve. Amounts due from related parties. Customer A [Member] Customer B [Member] Customer C [Member] Customer D [Member] Total Purchases [Member] Supplier A [Member] Supplier B [Member] Supplier C [Member] Schedule of Supplemental Balance Sheet Information Related to Leases [Table Text Block] Schedule of Supplemental Cash Flows Information Related to Leases [Table Text Block] Revenue recognized in excess of amounts paid or billed (account receivable) to the Group on uncompleted contracts. Jiangshan BVI [Member] HK Changfeng [Member] Liyun Holding Limited [Member] Beijing Junxinyuan Technology Development Co. Ltd. [Member] Shareholder [Member] Motor vehicles [Member] Electronic devices, furniture and office equipment [Member] Prepayment for inventories and others. Loan Facility Agreement [Member] Cash and cash equivalents and time deposits. Accrued service fee Accrued supplier deposit for quality. Accrued liabilities to suppliers. Julong Online (Beijing) Technology Development Co., Ltd. [Member] Datongyi Holding Limited Member] Qiren Holding Limited [Member] Convenience translations policy text block. Deferred offering costs policy text block. Engineering Solution Service [Member] System Maintenance Revenue [Member] Schedule of Allowance for Doubtful Accounts Related to Accounts Receivable Table Text Block The entire disclosure of recent accounting pronouncements. Payments received or receivable in excess of revenue recognized on uncompleted contracts. The disclosure of contract with customer asset and liability. Concentration of suppliers amount. Deferred tax assets valuation allowance additions. Deferred tax assets operating lease liabilities. Income tax reconciliation income tax expense benefit at tax effect of preferential tax rate. Proceeds from over allotment option. Beijing Yihai Construction Engineering Co Ltd [Member] Beijing Jianlei International Decoration Engineering Co Ltd [Member] Wu Yue [Member] Schedule Of Major Related Parties And Their Relationships [TableTextBlock] Beijing Huiju Tianxia InvestmentCo Ltd [Member] High And New Technology Enterprises [Member] Total operating lease assets. Engineering Solutions of Intelligent Projects [Member] Operation and Maintenance of Intelligent Projects [Member] Sales of Equipment and Materials of Intelligent Systems [Member] Two-Tiered Profit One [Member] Two-Tiered Profit Two [Member] Effective income tax rate reconciliation at preferrential tax rate. Income loss from continuing operations before income tax extraordinary items noncontrolling interest. Assets, Current Assets, Noncurrent Assets Liabilities, Current Liabilities, Noncurrent Liabilities Common Stock, Share Subscribed but Unissued, Subscriptions Receivable Equity, Attributable to Parent Liabilities and Equity Gross Profit Operating Expenses Comprehensive Income (Loss), Net of Tax, Attributable to Parent Shares, Outstanding Increase (Decrease) in Accounts Receivable Increase (Decrease) in Other Receivables Increase (Decrease) in Prepaid Expense and Other Assets Increase (Decrease) in Contract with Customer, Asset Increase (Decrease) in Due from Related Parties, Current Increase (Decrease) in Deferred Charges Increase (Decrease) in Other Noncurrent Assets Increase (Decrease) in Accounts Payable, Trade Increase (Decrease) in Other Accounts Payable and Accrued Liabilities Increase (Decrease) in Income Taxes Payable Increase (Decrease) in Contract with Customer, Liability Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Payments to Acquire Productive Assets Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Payments of Financing Costs Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Lessee, Leases [Policy Text Block] Contract with Customer, Receivable, before Allowance for Credit Loss, Noncurrent Contract with Customer, Asset, Allowance for Credit Loss, Noncurrent Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Accrued Liabilities and Other Liabilities Lease, Cost Operating Lease, Payments OperatingLeaseAssets Operating Lease, Liability Deferred Tax Assets, Gross Deferred Tax Assets, Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance Deferred Tax Assets, Net Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Related Party Transaction, Amounts of Transaction Other Receivables