It has been reported that vitamins A and E and Se affected the reproductive performance and some biochemical parameters in ewes, and the numbers, concentration and motility of spermatozoa in rams. In addition, Se and vitamin E have important functions in the etiology of WMD. Therefore, this study was designed to investigate the effects of vitamin A and E and Se supplementation on reproductive performance and some biochemical parameters in ewes, and birth weight and survival rates of lambs. Four groups were formed (A, B, C, D) and fed with a vitamin A, E and Se supplemented diet as follows. Group A (Control): It was fed with pasturage+concentrate feed+hay-trefoil, Group B (Vitamin A): It was fed with pasturage+concentrate feed+hay-trefoil+ Vitamin A (15000 IU/kg), Group C (Vitamin A+E+Se): It was fed with pasturage+concentrate feed+hay-trefoil+Vitamin A (15000 IU/kg), E (250 mg/kg), Se (0.3 mg/kg), Group D (Vitamin E+Se): It was fed with pasturage+concentrate feed+hay-trefoil+ Vitamin E (250 mg/kg), Se. (0.3mg/kg). Biochemical parameters of all ewes were determined at the beginning of the study and in late pregnancy. The weights of the lambs were measured by scales during the first month. There was no statistically significant difference between the values of control and the other groups before supplementation of vitamin A, E and Se in the diet. In late pregnancy the concentrations of serum glucose in groups C (Vit A, E, Se) and D (Vit E and Se), total protein in groups B (Vit A) and D (Vit E and Se), cholesterol and albumin in groups D, LDH in groups B (Vit A) and D were significantly higher (P<0.01, 0.03, 0.01, 0.02, 0.01 respectively) than those of the control group. The concentrations of serum urea in groups C and D were significantly lower (P<0.03) than those of the control group. In addition, the weights of lambs in group D- (Vit E and Se) were higher (P<0.01) in the 4th week than those of the control group. In conclusion, it was determined that vitamins A and E and Se supplementation had significant effects on some biochemical parameters of ewes. There was no different in reproductive performance among the groups.