Khat is chewed traditionally in Ethiopia, Somalia, Yemen and Kenya. In Ethiopia, khat chewing is now becoming an everyday substance of abuse for the general population. Knowledge about the effects of khat chewing on blood glucose levels is very sparse. Therefore, the objective of this study was to investigate the effect of fresh juice of khat (Catha edulis) on blood glucose levels of normal and streptozocin-induced diabetic rats. Sixteen normal and 24 diabetic male wistar rats were studied. Diabetic rats were divided into three groups: group I were treated with 4.5 ml/kg of fresh juice of Catha edulis (N=8). Group II were treated with glibenclamide (5 mg/kg) (N=8), group III were treated with distilled water which served as controls. Normal rats were divided into two groups: group I were given 4.5 ml/kg of fresh juice of Catha edulis (N=8) and group II were given distilled water as a control. The rats in each group was orally administered with single dose of fresh juice, glibenclamide or distilled water daily and blood glucose was measured at 0, 2 and 4 h on day 1, thereafter fasting blood glucose was measured in daily basis for first two weeks and once weekly on every 5th day in the following four weeks. Oral administration of a fresh juice of Catha edulis in diabetic and normal rats reduced the fasting blood glucose level from 223.7 ± 27.6 and 115.4 ± 2.48 mg/dl at baseline to 106 ± 18.2 and 79.6 ± 3.41 mg/dl, respectively at the end of study (p<0.05). Administration of fresh juice of Catha edulis in diabetic and normal rats respectively decreased blood glucose levels from 282.4 ± 45.5 and 95.2±6.2 mg/dl at baseline to 164.5 ± 31.6 (p <0.05) and 67.6 ± 6.8 mg/dl (p <0.05) at 4 h. It also decreased body weight in diabetic and normal rats from 304.81 ± 14.46 and 214 ± 17.84 g at baseline to 237.37 ± 12.28 (p <0.05) and 160.8 ± 15.49 g (p <0.05) at 4th wk., respectively. In summary, oral administration of a fresh juice of Catha edulis exerts a hypoglycemic effect and weight reduction in normal and streptozocin-induced diabetic rats. Further studies to isolate different active components of Catha edulis and to elucidate the exact mechanism of action are recommended.