Document And Entity Information (USD $)	6 Months Ended
	Jul. 31, 2011	Sep. 01, 2011
Entity Registrant Name	MET PRO CORP
Entity Central Index Key	0000065201
Current Fiscal Year End Date	--01-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float	$ 154,511,604
Entity Common Stock, Shares Outstanding		14,659,545
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q2
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jul. 31, 2011