Ocimum sanctum (OS) has been mentioned in Indian system of traditional medicine to be of value in the treatment of diabetes mellitus. We have previously shown that OS shows a dose-dependent hypoglycemic effect and prevented rise in plasma glucose in normal rats. It also showed significant antihyperglycemic effect in STZ-induced diabetes. The present study was undertaken to assess the effect of OS on three important enzymes of carbohydrate metabolism [glucokinase (GK) (EC 188.8.131.52), hexokinase (HK) (EC 184.108.40.206) and phosphofructokinase (PFK) (EC 220.127.116.11)] along with glycogen content of insulin-dependent (skeletal muscle and liver) and insulin-independent tissues (kidneys and brain) in STZ (65 mg/kg) induced model of diabetes for 30 days. Administration of OS extract 200mg/kg for 30 days led to decrease in plasma glucose levels by approximately 9.06 and 26.4% on 15th and 30th day of the experiment. Liver and two-kidney weight expressed as percentage of body weight significantly increased in diabetics (P<0.0005) versus normal controls. OS significantly decreased renal (P<0.0005) but not liver weight. Renal glycogen content increased by over 10 folds while hepatic and skeletal muscle glycogen content decreased by 75 and 68% in diabetic controls versus controls. OS did not affect glycogen content in any tissue. Activity of HK, GK and PFK in diabetic controls was 35, 50 and 60% of the controls and OS partially corrected this alteration.