Document and Entity Information - shares	3 Months Ended
	Dec. 31, 2018	Feb. 01, 2019
Document and Entity Information [Abstract]
Entity Registrant Name	APPLIED DNA SCIENCES INC
Entity Central Index Key	0000744452
Trading Symbol	apdn
Current Fiscal Year End Date	--09-30
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		36,362,057
Document Type	10-Q
Document Period End Date	Dec. 31, 2018
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Entity Small Business	true
Entity Emerging Growth Company	false