DOCUMENT AND ENTITY INFORMATION	6 Months Ended
	Jan. 31, 2013	Mar. 08, 2013
Entity Registrant Name	GENEREX BIOTECHNOLOGY CORP
Entity Central Index Key	0001059784
Current Fiscal Year End Date	--07-31
Entity Filer Category	Accelerated Filer
Trading Symbol	gnbt
Entity Common Stock, Shares Outstanding		490,001,537
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jan. 31, 2013
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2013