Document And Entity Information - shares	3 Months Ended
	Aug. 31, 2020	Oct. 15, 2020
Document Information Line Items
Entity Registrant Name	BIOMERICA INC
Document Type	10-Q
Current Fiscal Year End Date	--05-31
Entity Common Stock, Shares Outstanding		11,752,589
Amendment Flag	false
Entity Central Index Key	0000073290
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Aug. 31, 2020
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Interactive Data Current	Yes