Effect of Nigella sativa and Carthamus tinctorius L. oils on some biochemical parameters was investigated in streptozotocin (STZ)-induced diabetic male Wistar rats. STZ-induced diabetic rats showed significant increases in the levels of blood glucose, triglycerides, cholesterol, low density lipoprotein LDL-cholesterol , creatinine, urea, alanine aminotransferase (ALT) and aspartate aminotransferase (AST), while body weight , high density lipoprotein HDL-cholesterol, total protein levels were significantly decreased compared to normal rats.Administration of the tested oils to diabetic rats resulted in a significant decrease in blood glucose, triglycerides, cholesterol, LDL-cholesterol, urea, AST and ALT while body weight and HDL-cholesterol level was markedly increased after three weeks compared to untreated diabetic rats. The results of this study indicate that the tested oils possess hypoglycemic, hypolipidemic and antioxidant effects in STZ-induced diabetic rats.