The hypoglycemic effect of the aqueous (Aq) extract of the bark of Pterocarpus marsupium (PM) and alcoholic (Alc) extract of seeds of Trigonella foenum-graecum (FG) and leaves of Ocimum sanctum (OS) was investigated in both normal and alloxan-induced diabetic rats. The Aq extract of PM (1 g/kg PO) significantly (P<0.001) reduced the blood sugar levels from 72.32+/-5.62 to 61.35+/-1.2 mg% 2 h after oral administration of the extract and also significantly lowered the blood glucose in alloxan diabetic rats from 202.91+/-5.44 to 85.22+/-11.28 mg% 21 days after daily oral administration of the extract (P<0.001). Similarly, reduction was seen with Alc extract of FG (74.33+/-4.77 to 60.56+/-1.9 in normal rats and 201.25+/-7.69 to 121.25+/-6.25 in diabetic rats) (P<0.001) and OS (204.48+/-11.0 to 131.43+/-7.86 in normal rats and 73.54+/-3.7 to 61.44+/-2.3 in diabetic rats) (P<0.001). In addition, the extract also showed a favorable effect on glucose disposition in glucose fed hyperglycemic rats.