The blood glucose lowering activity of the Polyherbal preparation-I (1:1:1 of Wheat germ oil, Coraidrumsativum and Aloe vera) was studied in normal rats after oral administration at doses of 1.0 ml/kg and 2.0 ml/kg and Polyherbal preparation-I,II (Wheat germ oil, fresh juice of Coriandrumsativum and Aloe vera in the ratio of 1:2:1), and III (Wheat germ oil, fresh juice of Coriandrumsativum and Aloe vera in the ratio of 2:2:1) on alloxan-induced diabetic rats, after oral administration at doses of 1.0 ml/kg and 2.0 ml/kg. Blood samples were collected from tail vein method at 0, 0.5, 1, 2, 4, 8, 12, and 24 h in normal rats and in diabetic rats at 0, 1, 3, 7, 15 and 30 days. Blood plasma glucose was estimated by GOD/POD (Glucose oxidase and peroxidase) method. The data was compared statistically by using one way ANOVA method followed by Dunnett multiple component test. Statistical significance was set at P<0.05. KEY WORDS: Blood plasma glucose level, Alloxan-induced diabetes.