Prolonged exposure to high temperature increases oxidative stress in the male reproductive tract, reducing sperm quality and contribute to male infertility. Vitamin E, a potent antioxidant, is used therapeutically to counter many pathologies that are related to oxidative stress. It is not known whether vitamin E can help to preserve fertility during exposure to heat stress. Hence, this study was designed to investigate whether dietary supplementation with vitamin E would preserve male reproductive capacity in Drosophila melanogaster during exposure to heat stress. For 15 days, adult male flies were exposed to either room temperature continuously (RT; 25°C, n = 96) or to heat stress for eight hours each day, and 25°C for the other 16 hours per day (HS; 34°C, n = 96) and fed one of four levels of vitamin E in the food (0, 10, 100, or 1,000 μg/mL). After treatment, half of the flies from each treatment group (n = 12) were placed individually into vials with one virgin female. Their reproductive capacity was assessed by counting the number of eggs and the number of offspring in each vial. The remaining flies from each treatment group (n = 12) were used to evaluate the average size of the seminal vesicles and sperm DNA fragmentation. Heat stress reduced the number of eggs, offspring, and seminal vesicle size (P<0.05), and the effect was partially rescued by vitamin E supplementation (P < 0.05). Compared to heat stressed males without vitamin E, those supplemented with 100 µg/mL vitamin E during heat stress had a lower percentage of sperm with DNA fragmentation. Overall, we conclude that vitamin E can help to maintain the reproductive capacity of male D melanogaster during exposure to heat stress. Whether mammals, including humans, similarly benefit from antioxidant supplementation during exposure to higher temperatures remains to be established.