Abstract Background: Valproate (VPA) is used as an antiepileptic drug for the treatment of generalized and partial epilepsy and as a prophylaxis for the febrile convulsions of childhood. Aim of Study: This study evaluated the protective effect of L cysteine on valproate-induced testicular abnormalities in male Wistar rats. Material and Methods: A total of 30 rats were grouped into three groups, each having 10 animals. Sodium valproate (500mg/kg) was given intraperitoneally for 10 days alone in group II and in accompany with L cysteine (100mg/kg) was given orally in group III with additionally a control group given only saline. On day tenth, all animals were sacrificed and the different parameters were recorded. Results: The histopathological examination revealed that valproate had caused degeneration and desquamation of germinal cells in the epithelium, edema and congestion. These degenerative changes were significantly improved by giving L cysteine. The apotosis and the oxidative stress were suggested by our study to be the causative mechanisms of Valproate testicular toxicity as proved by CASPASE-3 reaction and the GSH and MDA levels which were significantly improved by giving L cysteine as antioxidant. Conclusion: This study supposed that VPA disturbs the testicular histology due to its toxicity by inducing oxidative stress, but the LC could improve these side effects.