Objective:To estimate the hypoglycemic effects of the alcohol extract from the leaves of Rhus Typhina (TLEEP) in vitro and in vivo. MethodsIn vitro experiment, the effects of TLEEP on the activity of alpha-glucosidase were observed. In vivo experiment, diabetic model was induced by streptozocin (STZ) in male Kunming mice. The model rats were then divided into the following groups:model control group, positive control group 1 (acarbose group 6.66 μg·g-1·d-1), positive control group 2 (Xiaoke pill group 390 μg·g-1·d-1) and low-, medium-, high-dose of TLEEP group (200,0, 800 μg·g-1·d-1). Each group had 10 rats, and received 3-week treatment. After treatment, the blood was taken from the eyes to detect serum insulin, blood lipid (TG, TC, HDL-C, LDL-C), hepatic glycogen, and the sugar tolerance.  Results:The results of in vitro experiment showed that TLEEP (0.4 g·L-1) inhibited the activity of alpha-glucosidase by 91%, with significant inhibition of alpha-glucosidase activity. The results of in vivo experiments showed that TLEEP, especially the high-dose TLEEP significantly reduced the blood glucose of model mice. The TLEEP significantly improved the serum insulin level and hepatic glycogen content, reduced serum levels of TC, TG and LD-C(P<0.05), and improved the HDL-C content (P<0.05) of model mice.  Conclusion: TLEEP can markedly decrease blood glucose and improve the lipid metabolism disorders in STZ-induced diabetic mice. The TLEEP is a natural herb with potential hypoglycemic activities.