Document And Entity Information (USD $)	3 Months Ended
	Oct. 29, 2011	Jan. 29, 2011
Entity Registrant Name	ECOLOGY & ENVIRONMENT INC
Entity Central Index Key	0000809933
Current Fiscal Year End Date	--07-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	No
Entity Filer Category	Smaller Reporting Company
Entity Public Float		$ 37,293,225
Entity Common Stock, Shares Outstanding	4,240,729
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jan. 02, 2012