The study was conducted at the period of 22/1/2018 to 13/1/2019 by using 82 Awassi ewes in late gestation period to determine the combined effect of melatonin receptor gene polymorphism (MTNRA1) three doses of vitamin E on litter size and lambs weight at birth and weaning. Results showed a significant effect (P<0.05) of MTNRA1 polymorphism on liter size , the highest value was noticed in ewes with CC genotype while the lowest value was in ewes with TT genotype namely,1.184 and 1.137 lamb respectively. Litter size were affected significantly (P<0.05) by vitamin E supplementation, the higher litter size was noticed in ewes that injected with 450IU/ week namely, 1.24lamb. Body weight of lambs at birth and weaning and average weight gain from birth to weaning differed significantly according to vitamin E supplementation. Significant differences (P<0.05) among combinations on all traits that studded. Ewes with CC or CT and supplemented of 900IU of vitamin E were the highest liter size (1.24 lamb). The ewes with genotype CC and supplemented 450IU of vitamin recorded the highest body weight of lambs at birth, body weight of lambs at weaning and average weight gain from birth to weaning namely, 4.30, 16.84 and 12.54 kg respectively.