In recent years, several plant extracts have been examined for their ANTIDIABETIC propertics in an effort to identify alternative treatment strategies that pose less of a risk for diabetics. The present study was undertaken to investigate the ANTIDIABETIC EFFECTs of Syzygium cumini bark in experimental diabetes mellitus.Materials and Methods: Diabetes was induced in male albino Wistar rats by a single intraperitoneal injection of streptozotocin (45 mg/kg body weight), after which, the animals were randomly allocated into five experimental groups as follows: Group 1: normal rats, Group 2: normal rats received Syzygium cumini bark extract (SBEt; 300mg/kg body weight), Group 3: diabetic control rats, Group 4: diabetic rats receiving SBEt (300mg/kg), Group 5: diabetic rats received glibenclamide (600μg/kg body weight). The EFFECTs of 45 days treatment of SBEt on blood glucose, plasma insulin, C-peptide, urine sugar and body weight were studied in comparison to those of glibenclamide.Results: Blood glucose levels (268.10±19.25 mg/dL) and urine sugar increased significantly whereas the levels of plasma insulin (5.01±0.29 μU/L) and C-peptide (167.68± 8.50 pmol/L) decreased significantly in diabetic rats as compared to normal rats. Oral administration of SBEt exhibited ANTIDIABETIC activity by significantly (p<0.05) lowering blood glucose (84.30±4.25) and urine sugar levels in diabetic rats. Additionally, diabetic rats treated with SBEt had significantly (p<0.05) elevated levels of plasma insulin (10.29±0.59) and C-peptide (236.50±11.87). During OGTT, long-term administration of SBEt was able to significantly (p<0.05) decrease blood glucose concentrations (93.94 ± 3.17; 120min) at various time intervals when compared to the OGTT pattern of diabetic rats (316.03 ± 18.03). As compared to glibenclamide, SBEt has better ANTIDIABETIC EFFECTs.Conclusions: The findings of this study indicate that the ANTIDIABETIC activity of SBEt, and both the pancreatic and the extrapancreatic mechanisms might be involved such apparent dual actions of SBEt would be more advantageous to the existing oral ANTIDIABETIC monotherapy.