摘要Objective: To investigate the effect of Citrillus lanatus (C. lanatus) seeds and caffeine on blood glucose levels and testicular functions of alloxan-induced diabetic male Wistar rats. Methods: Alloxan was administered at a single dose of 150 mg/kg BW to induce diabetes. A dose of either 200 mg/kg C. lanatus or 100 mg/kg caffeine or both was administered daily to alloxan-induced diabetic rats for three weeks, after which results were compared with a normal control group and a positive control group that received both alloxan and glybenclamide. Results: C. lanatus seeds extract significantly decreases (P<0.05) blood glucose level and significantly (P<0.05) increased sperm motility, sperm count, normal sperm morphology, sperm viable cells and testosterone in plasma level of alloxan-induced diabetic rats treated with C. lanatus seed extract and caffeine. Conclusions: The present study showed that co-administration of caffeine and hydromethanolic fraction of C. lanatus seed extract have hypoglycemic effect and may consequently ameliorate the impaired testicular general architecture and inhibits sperm death or testicular damage caused by alloxan-induced diabetes.