ABSTRACT The present work was aimed to investigate the possible antioxidant and hypoglycemic effects of broccoli on obese diabetic rats. Thirty adult male Sprague-Dawley rats were divided randomly into six equal groups (n=5) as follows: Group 1: negative control, was fed on a basal diet. Groups 2-6 were fed High fat diet (HFD) for 6 weeks to induce obesity. The obese rats were then rendered diabetic by subcutaneous injection with a single dose of alloxan (120 mg/kg). Group 2 was kept as a positive control group (obese diabetic rats) and groups 3, 4, 5 and 6 fed on HFDs-alloxan induced diabetic and supplemented with 2.5, 5, 7.5 and 10% dried broccoli. At the end of the experiment, rats were scarified and serum was collected for biochemical analyses. The administration of HFD-alloxan group (control positive) resulted in significant elevations in body weight gain, feed efficiency ratio, peritoneal fat pad, serum total cholesterol, triglyceride, LDL-c, VLDL-c, leptin, glucose, insulin, interleukin-1 beta and malondialdehyde levels compared to negative control, and levels of serum HDL-c and glutathione peroxidase activity were significantly decreased. On the other hand, a supplemented diet with dried broccoli powder attenuated these adverse effects and biochemical alterations caused by HFD-alloxan administration. In conclusion, broccoli exhibits an antioxidant and hypolipidemic activity and was effective in reducing glucose level in obese diabetic rats. The study recommends that intake of broccoli may be beneficial for patients who suffer from diabetes and obesity.