Cyclophosphamide is a drug used for chemotherapy and as an immune-suppressive in the organ transplantation. Despite its many clinical implications in the treatment of cancers, this drug has toxic effects on the reproductive system. This study aimed to evaluate the effect of ghrelin against the damages caused by cyclophosphamide. In this experimental study, 40 male mice were randomly divided into four groups: (i) control; (ii) cyclophosphamide; (iii) cyclophosphamide + ghrelin; and (iv) ghrelin. Cyclophosphamide (100 mg/kg body weight), once a week, and ghrelin (80 μg/kg body weight), daily, were administered intraperitoneally for 5 weeks. After 5 weeks, the epididymides were removed and the lipid peroxidation, total antioxidant capacity and sperm parameters were examined. The fertility rate was evaluated by performance in vitro fertilisation. In the mice exposed to cyclophosphamide, the number of spermatozoa and viability, as well as total antioxidant capacity, decreased significantly (p < .05). The increase in the abnormal sperm and MDA levels was observed (p < .05). In addition, the fertility rate decreased in this group, while the use of ghrelin significantly improved the above disorders in the treatment group (p < .05). The findings of this study showed that ghrelin attenuates negative effects caused by cyclophosphamide in the sperm parameters and enhances the fertility.