Abstract: Background: Coccinia grandis (ivy gourd) an edible plant widely consumed in many Southeast Asian countries has been used traditionally for the treatment of diabetes mellitus. However, its role in the regulation of carbohydrate-digesting enzymes, especially α-amylase and α-glucosidase has not been clearly established. Materials and Methods: The aqueous leaf and stem extracts of Coccinia grandis (the CGL and the CGS extracts, respectively) were prepared and their actions toward in vitro activities of α-amylase and α-glucosidase were examined. The activities of α-amylase and α-glucosidase were indicated by the amounts of maltose and p-nitrophenol generated in the reactions, respectively. Results: The CGL and the CGS extracts possessed an α-amylase inhibitory action with the IC50s of 8.09±0.72 and 8.06±1.27 mg mL–1, respectively. The CGL extract produced a mixed inhibition against α-amylase, whilst the CGS extract inhibited the enzyme in an uncompetitive manner. The CGL and the CGS extracts exhibited an inhibitory action against α-glucosidase enzyme with the IC50s of 77.66±9.16 μg mL–1 and 0.75±0.11 mg mL–1, respectively. Both extracts acted as mixed enzyme inhibitors against α-glucosidase. Conclusion: These results support the traditional use of Coccinia grandis in diabetic patients, especially for the control of postprandial plasma glucose level. However, further studies on identification of the active phytochemicals acting as enzyme inhibitors and in vivo carbohydrate-digesting enzyme inhibition are required to verify its potential clinical use in diabetes mellitus.