total of thirty-six Saidi pregnant ewes at late pregnancy had almost similar average body weight (48kg) were divided at first before lambing into two groups control and treatment with vitamin D injection, each group 18 ewes. Ewes were assigned after lambing into 4 comparable groups (9 each) as follow, Group 1 (CC) Neither dams nor lambs treated with vitamin D, Group 2 (CT) Dams not treated, lambs treated, Group 3 (TC) Dams treated, lambs not treated and Group 4 (TT) Both dams and lambs treated. Treated ewes were injected three doses of vitamin D every week for three weeks by 500000 IU, while suckling lambs were injected vitamin D with 100000 IU after two weeks of birth and then every month until weaning. The objective of this study was to evaluate the impact of Vitamin D injection on daily gain of lambs and some reproductive traits of ewes. The obtained results indicate that:1-There are a significant effect of vitamin D injection on body weight (BW) of lambs. Vitamin D injection increased (P<0.05) BW by about 41.9, 68.9 and 99.8 in favor of CT, TC and TT groups, respectively. 2-Vitamin D supplemented lambs born to treated-ewes increased ADG by about 96%,. 3-Pregnancy period of vitamin D-treated ewes was longer than that of control ones (155.95 vs.143.65 day). Also, three doses of vitamin D injection during late pregnancy period improved fertility rates. 4-Vitamin D injection improved survival rate, while mortality rate, tended to be higher in lambs born to control ewes compared to those born to vitamin D-treated ewes. In Conclusion, Injection of vitamin D at late pregnancy of ewes may improve reproductive performance of ewes and their lamb survival.