Management of blood glucose level is the hallmark in the treatment of diabetes. Much work has not been done on the management of diabetes using the stem tuber extract of Colocasia esculenta. The objective of this study was to evaluate the antihyperglycemic and hematological parameter on Colocasia esculenta aqueous stem extract in alloxan induced diabetic rats. Sixty (60) male rats were used in the study. Seven days of acclimatization, the rats were divided randomly into six groups of five in each group. Group 1: Served as normal control, Group 2: Diabetic control group (negative control), Group 3: Diabetic group and “Glucinorm-M80” (positive control), Group 4: Diabetic group and extract at 200 mg/kg bodyweight, Group 5: Diabetic group and extract at 400 mg/kg, Group 6: Diabetic group and extract at 600 mg/kg. Diabetes was induced in albino rats by intraperitoneal injection of alloxan at a single dose of 120 mg/kg body weight in groups 2 to 6 after starving them for 24 hrs. The animals were given feed and water ad libitum. The albino rats were administered for twenty eight days with the aqueous Colocasia esculenta stem tuber, after which they were fasted overnight, anaesthetized with chloroform and sacrificed. The result showed that there was a significant increase (p<0.05) in mean body weight of the positive control and the treatment groups (200 mg/kg to 600 mg/kg) when compared with the negative control which has a significant decrease (p<0.05) in mean body weight. The result showed that there was a substantial decrease in blood glucose of animals administered with different doses of aqueous extract of Colocasia esculenta stem tuber and the positive control group. The result showed that a significant difference (P<0.05) in the concentrations of RBC, PCV, HB, PLT and MCH of the treatment groups and negative group when compared with the normal control group. Also there was a significant difference in glycosylate hemoglobin of the treatment groups when compared with the control group and negative group. This study has demonstrated that aqueous stem tuber extract of Colocasia esculenta has a significant increase on body weight which may have a role of improving the states of possible weight loss following complicated diabetes. Also, aqueous stem tuber extract of Colocasia esculenta has an ameliorative effect on sugar level and some hematological parameters of alloxan induced diabetic rats showing effective diabetic control and management of diabetes.