Male albino (Wistar) rats were used to study the ameliorative effects of Mangifera indica (M. indica) ethanolic extract at doses of 200 and 400 mg/kg respectively, glibenclamide (05 mg/kg) and sitagliptin (10 mg/kg) were used as standard drugs in streptozotocin (45 mg/kg) induced diabetic rats (positive control). The aim of the research study was to assess the biochemical changes in type II diabetic rats model treated with different doses of ethanolic leaves extract of M. indica. Biochemical parameters were included serum insulin concentration, serum transaminase levels, bilirubin levels and evaluate the histopathological examination of the liver. The results of the investigation revealed that the significant (p<0.001) increment of the serum insulin level in 200 and 400 mg/kg ethanolic extract of M. indica (treated groups). In streptozotocin diabetic rats, the activities of liver enzymes in serum were increased and after 28 days of treatment with 200 and 400 mg/kg ethanolic extract of M. indica, transaminase levels were effectively reduced. Histopathological study revealed hepatic histological changes which were more noticeable in diabetic inducer group. M. indica leaves extract have positive effective results on biochemical parameters in diabetic type II rats. The biochemical protective effects of M. indica were associated with improved histological hepatocellular integrity and architecture.