Cover - USD ($)	12 Months Ended
	Sep. 30, 2021	Dec. 27, 2021	Mar. 31, 2021
Cover [Abstract]
Document Type	10-K/A
Document Annual Report	true
Document Period End Date	Sep. 30, 2021
Current Fiscal Year End Date	--09-30
Document Transition Report	false
Entity File Number	1-10799
Entity Registrant Name	ADDvantage Technologies Group, Inc.
Entity Incorporation, State or Country Code	OK
Entity Tax Identification Number	73-1351610
Entity Address, Address Line One	1430 Bradley Lane
Entity Address, Address Line Two	Suite 196
Entity Address, City or Town	Carrollton
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75007
City Area Code	918
Local Phone Number	251-9121
Title of 12(b) Security	Common Stock, $.01 par value
Trading Symbol	AEY
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
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 22,959,185
Entity Common Stock, Shares Outstanding		12,739,686
Entity Central Index Key	0000874292
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Amendment Flag	true
Amendment Description	EXPLANATORY NOTEOn December 27, 2021, ADDvantage Technologies Group, Inc., an Oklahoma corporation, filed its Annual Report on Form 10-K for the fiscal year ended September 30, 2021 (the “Original Filing”). Certain Part III information was omitted from the Original Filing in reliance on General Instruction G(3) to Form 10-K. General Instruction G(3) to Form 10-K provides that a registrant may incorporate by reference certain information from a definitive proxy statement which involves the election of directors, if such definitive proxy statement is filed with the Securities and Exchange Commission (the “Commission”) no later than 120 days after the end of the registrant’s fiscal year. Alternatively, the registrant may provide this information in an amendment to the Form 10-K, if such amendment is filed with the Commission no later than 120 days after the end of the registrant’s fiscal year. Accordingly, this Amendment No. 1 on Form 10-K/A (this “Amendment”) supplements the Original Filing by amending and restating Part III, Items 10 through 14 of the Original Filing.Except as stated herein, this Amendment does not reflect events occurring after the filing of the Original Filing, and no attempt has been made in this Amendment to modify or update other disclosures as presented in the Original Filing.Throughout this Amendment, unless indicated otherwise, we refer to ADDvantage Technologies Group, Inc. and its subsidiaries as “we,” “us,” “our,” “ADDvantage,” “and the “Company”.