Abstract: The effect of different doses of Black caraway (Carum carvi L.) oil on the body weights of alloxan-induced diabetic rats was studied. Forty white male albino rats of the Winster strain weighing between 145-240 g were used for this study. Diabetes was induced in the experimental rats with alloxan (70 mg kg-1 body weight). Group 1 rats served as the normal control, group 2 served as the caraway control, whereas group 3 rats served as the diabetic control. Groups 4, 5, 6, 7 and 8 were the test groups. All the test groups were administered various doses of the black caraway oil ranging from 5, 10, 20, 40 and 80 mg kg-1 body weights, respectively. Group 2 (the caraway control) rats were administered 10 mg kg-1 body weight of black caraway oil. The duration of the experiment was 10 weeks. The weights of the animals in each group were recorded daily throughout the duration of the experiment. The blood glucose levels in the different groups were assayed. The results show that the normal control, the caraway control and the diabetic rats treated with 10 mg kg-1 body weight of black caraway oil showed progressive and steady increase in the % mean weekly body weights, while the diabetic untreated rats and the other test groups showed decreasing and alternating increments, respectively in the % mean weekly body weights. The blood glucose level in the 10 mg caraway treatment group was significantly reduced (p< 0.01) compared to the diabetic control and the other treatment groups. This shows that the black caraway oil increases the % mean weekly body weights of the diabetic/non-diabetic rats at a dose not more than 10 mg kg-1 body weight. It can also be inferred that the 10 mg kg-1 body weight of caraway oil is the safe dose that can be used in managing Diabetes mellitus. The information obtained from this study would be used in the management of diabetic patients.