Aim: Varicocele is an abnormal enlargement of the pampiniform venous plexus and blood blockage in the spermatic cord. Among major effects on male fertility is oxidative stress and metabolites reflex to testicles, which in turn have a significant part in producing free radicals (reactive oxygen species =ROS). As a micronutrient, selenium has an antioxidant characteristic to normal spermatogenesis and combats oxidative stress. The present study aimed at examining selenium effects, as an antioxidant element) on sperm parameters (sperm count, motility, morphology) in varicocele rats. Methods: This study was a case-control. It was done in 2017 in the Qazvin University of Medical Sciences on 24 male Rats that were divided randomly to four 6-subject groups of control, sham, varicocele, and treated varicocele. A daily 0.2-mg selenium diet was injected intraperitoneally to the treated varicocele group. After four weeks, sperm indices were examined among all the groups and the data was analyzed by one-way ANOVA. Results: All the indices in this study (sperm count, motility and morphology) had a significant decline in the varicocele group compared to the control group (p<0.05). Results also indicated an effect of selenium as an antioxidant on the number of sperm as well as their motility. This led to improvement of these parameters having no effects on sperm morphology among varicocele rats. Conclusion: Results showed that, as an antioxidant, selenium eliminated free radicals in varicocele rats indicating its effectiveness on varicocele-dependent infertility.