This research aim to find out the effect of M. tanarius leaf methanol-water extract (MTME) whether it can lowering blood glucose levels. This research was experimental study with one way-complete-random design using 25 male rats which divided into five groups. The rats in group I were given CMC 1% (negative control). The group II rats were given 0.45 g/kg BW dose of Glibenclamide (positive control). In group III, IV and V, the rats were given 0.43; 1.28; 3.84 g/kg BW doses of MTME orally. The hypoglycemic effect of MTME was tested by using the Oral Glucose Tolerance Test (OGTT) method. The blood-glucose contents were measured at the 0, 15, 30, 60, 90, 180, and 240 after the OGTT and treatment. The AUC were statistically analyzed using one way ANOVA and Scheffe test with 95 % convidence level. The result show that MTME at dose 0.43; 1.28; and 3.84 g/kg BW was effective in improving oral glucose tolerance.