| Cover - USD ($) $ in Millions | 12 Months Ended | ||
| Sep. 30, 2022 | Jan. 24, 2023 | Mar. 31, 2022 | |
| Cover [Abstract] | |||
| Document Type | 10-K/A | ||
| Amendment Flag | false | ||
| Document Annual Report | true | ||
| Document Transition Report | false | ||
| Document Period End Date | Sep. 30, 2022 | ||
| Document Fiscal Period Focus | FY | ||
| Document Fiscal Year Focus | 2022 | ||
| Current Fiscal Year End Date | --09-30 | ||
| Entity File Number | 001-36745 | ||
| Entity Registrant Name | APPLIED DNA SCIENCES, INC. | ||
| Entity Central Index Key | 0000744452 | ||
| Entity Tax Identification Number | 59-2262718 | ||
| Entity Incorporation, State or Country Code | DE | ||
| Entity Address, Address Line One | 50 Health Sciences Drive | ||
| Entity Address, City or Town | Stony Brook | ||
| Entity Address, State or Province | NY | ||
| Entity Address, Postal Zip Code | 11790 | ||
| City Area Code | 631 | ||
| Local Phone Number | 840-8800 | ||
| Title of 12(b) Security | Common Stock, $0.001 par value | ||
| Trading Symbol | APDN | ||
| Security Exchange Name | NASDAQ | ||
| Entity Well-known Seasoned Issuer | No | ||
| Entity Voluntary Filers | No | ||
| Entity Current Reporting Status | Yes | ||
| Entity Interactive Data Current | Yes | ||
| Entity Filer Category | Non-accelerated Filer | ||
| Entity Small Business | true | ||
| Entity Emerging Growth Company | false | ||
| Entity Shell Company | false | ||
| Entity Public Float | $ 17.2 | ||
| Entity Common Stock, Shares Outstanding | 12,908,520 | ||
| Auditor Name | Marcum LLP | ||
| Auditor Location | Melville, NY | ||
| Auditor Firm ID | 688 |
