Introduction: Quercetin is a herbal antioxidant commonly found in nature. It is frequently used as supplement because of its beneficial effects on health. Objective: The aim of this study was to analyze effects of chronic administration of quercetin on triglyceride and blood glucose levels on diet-induced obesity in rats. Methode: Male Wistar rats aged 8-weeks weighing ± 150 g were distributed randomly into five groups (n=4). As normal control, one group received standard diet. Four other groups were induced to become obese with high fat diet comprising chow, wheat, cholesterol, cholic acid, and pig fat (3:2:1:1:2) for 90 days. Then, three of four obese groups received standard diet and each group were treated with quercetin with doses of 2, 10, and 50 mg/kg body weight for 10 weeks, whereas one other group received standard diet only (obese control group). Finally, triglyceride and blood glucose levels were measured. Result: Significant blood glucose reduction was found in all three quarcetine-treated groups as compared to obese control group (p<0.05), but greatest reduction was found on the group treated with 50 mg/kg quercetine. However, although all quercetin-treated groups showed lower levels of triglyceride as compared to obese control groups, significant reduction was only achieved by group treated with 50 mg/kg quarcetin (p<0.05). Conclusion: Quercetin had beneficial effect for reducing blood glucose and triglyceride levels on diet-induced obesity in rats.