Sodium arsenite as an environmental pollutant has adverse effects on reproductive organs through inducing oxidative stress. The aim was to investigate the effects of curcumin as a potent antioxidant on the seminal vesicles histology in mice treated with sodium arsenite. Adult male Naval Medical Research Institute (NMRI) mice were randomly divided into 4 groups (n=6), control, Sodium arsenite (5mg/kg/day), Curcumin (15mg/kg/day) and Sodium arsenite+ Curcumin. Treatments were performed by intraperitoneal injections for a 5-week period. Finally, seminal vesicles were removed and their histological changes were evaluated using stereological methods. The results were analyzed using one-way ANOVA and Tukey's test and the means were considered significantly different at p<0.05. A significant reduction in the mean total volume of seminal vesicle and mean volume of vesicular fluid and also a significant increase in connective tissue volume were observed in sodium arsenite group when compared to the control ones. The mentioned parameters were compensated in the sodium arsenite + curcumin group to the control mice. We did not find significant changes in the mean volumes of the parenchyma, epithelial cells, vessels, and muscular tissue by comparing the groups. Our results showed that curcumin could compensate the adverse effects of sodium arsenite on the mice seminal gland; therefore addition of curcumin (turmeric) to the daily diet of people in industrial cities could protect them from adverse effects of environmental pollutants like arsenic.