Acid, alkaline and enzymatic hydrolysis of agricultural crop wastes were compared for yields of total reducing sugars with the hydrolysates being evaluated for ethanol production using a mixed culture of Zymomonas mobilis and Candida tropicalis. Acid hydrolysis of fruit and vegetable residues gave 49-84 g reducing sugars l(-1) and 29-32 g ethanol l(-1) was then obtained. Alkaline hydrolysis did not give significant amount of reducing sugars. Enzymatic hydrolysis of fruit and vegetable residues yielded 36-123 g reducing sugars l(-1) and 11-54 g ethanol l(-1).