Cisplatin (Cis) is a treatment for testicular germ-cell tumors (TGCTs). Unfortunately, it causes testicular toxicity due to releasing reactive oxygen species (ROS) causing damage to testicular cells and chromosomes. The current study aimed to investigate the ameliorative effect of selenium nanoparticles (SeNPs) against cisplatin testicular toxicity in male rats by assessment of body weight, testis weight, oxidative stress markers in testis homogenates as (malondialdehyde (MDA), Superoxide dismutase (SOD), Glutathione reduced (GSH), Glutathione peroxidase (GSH ∼ PX) and Catalase (CAT)), gene expression, testosterone concentration (T), sperm characteristics (count, motility and abnormality) and testicular histopathology. Methods: Thirty adult male rats divided equally into four groups; a single dose intraperitoneally injection of cisplatin (10 mg/kg) and selenium nanoparticles (2 mg/kg/day) were administrated alone or in combination. Cis group showed a decrease in body weight, testis weight, antioxidant activities (SOD, GSH, GSH ∼ PX and CAT), T concentration and steroidogenetic expression, the data recorded an increase in MDA levels and sperm abnormality, meanwhile histopathology of testis sections showed degenerative changes in the seminiferous tubules. The co-administration of selenium nanoparticles ameliorated the harmful effects of cisplatin. In conclusion; SeNPs through its antioxidant potential may be useful to prevent the testicular toxicity induced by cisplatin to the rat testis by reducing oxidative stress.