Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Nov. 03, 2020
Entity Listings [Line Items]
Entity Registrant Name	ACM Research, Inc.
Entity Central Index Key	0001680062
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-38273
Entity Tax Identification Number	94-3290283
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	42307 Osgood Road, Suite I
Entity Address, City or Town	Fremont
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94539
City Area Code	510
Local Phone Number	445-3700
Title of 12(b) Security	Class A Common Stock, $0.0001 par value
Trading Symbol	ACMR
Security Exchange Name	NASDAQ
Class A Common Stock [Member]
Entity Listings [Line Items]
Entity Common Stock, Shares Outstanding		16,662,218
Class B Common Stock [Member]
Entity Listings [Line Items]
Entity Common Stock, Shares Outstanding		1,802,606