This study was performed to determine the effects of Aloe vera gel (AVG) from the leaves of Aloe barbadensis which is commercially available product in the market for human use, on male reproductive tract of Swiss albino mice. Male mice aged 4 weeks separated into four groups randomly received AVG by gavage daily for 28 days. The groups were as follows (n=5): control, ×0.5 dose group received half of recommended AVG dose, ×1 dose group received recommended AVG dose, and ×2 dose group received twice of recommended AVG dose. LH levels of mice in treatment groups decreased compared to control. Testosterone (T) levels decreased in ×2 dose group compared to control. Sperm head count did not change and sperm shape abnormalities in high dose group increased. Histo- pathological analysis showed that there were atrophic tubules, germ cell debris, picnotic cells and Sertoli cell vacu- olization in testes of high dose groups. In prostate glands, atrophic tubules and mononuclear cell infiltration were observed. There were no changes in malondialdehyde and reduced glutathione levels of testes among groups. The findings of this study indicate that oral usage of AVG may cause adverse effects on the male reproductive tract of mice by affecting the secretion of reproductive hormones.