This study aims to evaluate the therapeutic action of administration of Nigella sativa (NS) and Peganum harmala (PH) oils in diabetes and hepatic toxicity. Results show that treatment of diabetic rats with NS oil or PH oil ameliorate hyperglycaemia induced stress oxidative and hepatic dysfunction in diabetic rats. Administration of NS or PH oil to diabetic rats caused an anti-diabetic and antioxidant activities by the decrease in plasmatic glucose level and increase in hepatic superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities, reduced glutathione (GSH) and glycogen contents compared to untreated diabetic rats. Besides, NS and PH oils protect the hepatic function observed by decrease of triglyceride (TG), total cholesterol (TCh), and increase of high density lipoprotein-cholesterol (HDL-Ch) levels in serum and hepatic tissues. Moreover, a diminution in the bilirubin, transaminase glutanic pyruvic (TGP), and transaminase pyruvic oxaloacetic (TPO) contents in serum and the thiobarbituric acid-reactive substances levels (TBARs) in hepatic tissues are also detected.