The aim of the study was to verify whether an increased supply of vitamins E and C prevents the detrimental effects of ozone on the testes. The experiment was performed on 5-month-old rats exposed to ozone (0.5 ppm) for 50 days (5 h daily). Simultaneously, the animals were injected with the vitamins in 5-day intervals and at different doses (0.5, 1.5, 4.5, 5 and 15 mg of vitamin E; 0.5, 3, 9, and 50 mg of vitamin C; or both vitamins together, respectively). Gonad sections were PAS stained. In the ozonized males, depletion of germ cells occurred. In the vitamin E groups, the testes were comparable to the controls, excluding the 0.5-mg-dose vitamin E group in which perivascular fibrosis and intertubular hyalinization were observed. In the vitamin C groups, intertubular hyalinization, partial arrested spermatogenesis, and desquamation of the seminiferous epithelium appeared proportionall to the vitamin dose. Additionally, premature spermiation was found at a vitamin C dose of 50-mg. In the rats injected with both vitamins, hyalinization and fibrosis appeared in addition to partial arrest of spermatogenesis and vacuolar degeneration. In conclusion, vitamin E protects against the detrimental effects of ozone in rat testes irrespective of the dose applied. This was not observed for vitamin C. Moreover, administration of higher doses of vitamin C intensified the damage to the testes caused by ozone.