BACKGROUND: Oxidative stress is involved in pathogenesis of Polycystic Ovary Syndrome (PCOS). Lutein is a herbal compounds with antioxidant properties. OBJECTIVES: The current research aimed to evaluate the effect of lutein on body weight and histomorphometry of uterus in experimental PCOS induced with Dehydroepiandrosterone (DHEA) in mouse models. METHODS: Twenty-four female NMRI mice aged 20 days and weighing 14-17 g were randomly assigned to four equal groups: control, experimental PCOS, and PCOS treated groups with 125 and 250 mg/kg lutein. The induction period of PCOS with oral administration of DHEA (6 mg/100 g, daily) was 21 days and lutein treatment was followed by the induction period of 28 days. The mean body weight of the groups was evaluated on day 0, day 21 (at the end of DHEA treatment), and day 49 (at the end of treatment period) with lutein. The mean diameter of the uterine wall, the mean overall thickness of the uterine wall, the average thickness of the endometrium, myometrium and uterine epithelium, along with the number of endometrial gland branches were measured utilizing light microscope. RESULTS: The results revealed that body weight in the PCOS group was significantly higher than that in the control group on days 21 and 49. Treatment with 125 and 250 mg/kg of lutein reduced body weight in the lutein treated groups compared with PCOS (p < /em><0.01). The mean uterine wall diameter, mean total uterine wall thickness, mean thickness of endometrium, myometrium, and uterine epithelium with the number of uterine endometrial branching were significantly lower in the control and lutein treated groups compared to those in the PCOS group (p < /em><0.05). The use of both doses of lutein (125 and 250 mg / kg) significantly improved uterine histopathological indices, particularly the mean uterine wall diameter (p < /em>=0.0001) compared to the PCOS group. CONCLUSIONS: Lutein could improve the side effects of induced PCOS by DHEA on body weight and uterine parameters.