Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2018	Dec. 14, 2018	Mar. 31, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	APPLIED DNA SCIENCES INC
Entity Central Index Key	0000744452
Trading Symbol	apdn
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Current Fiscal Year End Date	--09-30
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
Entity Common Stock, Shares Outstanding		30,112,057
Entity Public Float			$ 38
Document Type	10-K
Document Period End Date	Sep. 30, 2018
Amendment Flag	false
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false