OBJECTIVES:To study the antidiabetic activity of Pleurotus ostreatus in normal and alloxan-induced diabetic mice. MATERIALS AND METHODS:Ethanolic extract of fruiting bodies of P. ostreatus was tested for their antidiabetic activity. BALB/C mice (25-30 g) were divided into four groups of six animals each normal control mice, diabetic control mice, diabetic mice posttreated with standard drug glibenclamide and diabetic mice treated with P. ostreatus ethanolic extract. Blood glucose level, biochemical parameters such as serum total cholesterol, LDL, HDL, VLDL, triglyceride creatinine, urea, and Serum glutamate oxaloacetate transaminase and Serum glutamate pyruvate transaminase were studied in alloxan-induced diabetic mice after 15 days of treatment. RESULTS:Animals treated with the ethanolic extract of P. ostreatus showed a significant decrease in serum glucose level (p < 0.01). The posttreatment with P. ostreatus extract reduced serum cholesterol, triglyceride and LDL-cholesterol. The serum HDL cholesterol was significantly increased in posttreated groups. The serum creatinine, urea levels were significantly reduced in posttreated group, whereas the decrease in the body weight was arrested by administration of P. ostreatus extract to the animals. DISCUSSION AND CONCLUSION:The consumption of P. ostreatus produced a significant hypoglycemic effect in diabetic mice and it is capable of improving hyperlipidemia and the impaired kidney functions in alloxan-induced diabetic mice. Thus, indicating that the ethanolic extract of P. ostreatus could be added in the list of medicinal preparations beneficial in diabetes mellitus.