The goal of this investigation is to determine the effect of treatment with vitamin E and selenium on mastitis, retained placenta and post-partum reproductive parameters in Egyptian Baladi cows during the late gestation period. Twenty four Baladi cows were used and divided into two groups of 12 for each. The first group injected with vitamin E and selenium component intramuscular at a rate of 1. 0 ml/30kg (BW) live body weight and the second group used as a control. Injected cows received two doses of (vitamin E and selenium component) in 14 and seven days prepartum. Cows were mated naturally just demonstration estrus symptoms. Rectal palpation was performed after two months days post- mating to pregnancy diagnosis. The findings showed an association between treated cows during late gestation with vitamin E and selenium and incidence rate of mastitis and retained placenta. Improved reproductive parameters in treated cows compared with untreated cows. In conclusion, the present study recommends that small breeders offer vitamin E and selenium in hot months during late gestation under the Aswan governorate environmental condition to minimize reproductive disorder and improve their cows' reproductive efficiency.