This study aimed to evaluate selenium supplementationeffect on induction of twinning of Barki ewes by using two different doses of PMSG in estrus synchronization program during the breeding season. For the experiment, 28 ewes were randomly divided into four groups, 7 ewes in each group, all ewes were treated with intra-vaginal sponges, containing 60 mg medroxy progesterone acetate for 14 days, immediately after sponge withdrawal, PMSG hormone at a doses of 250 IU in groups I, II and 750 IU in groups III and IV were administered intramuscularly. Selenium (Se) levels were 0.05 mg/kg diet DM (without supplementation) for groups I and III and 0.2 mg /kg diet DM for groups II and IV (Se supplementation). The pregnancy and barren rates for groups I, II, III and IV were (57.14%, 100%, 71.43% and 85.71 %) and (42.86%, 0.0%, 28.57% and 14.29%), respectively (P<0.01). At the same time, the twinning rate was (0%, 71.43%, 42.86% and 71.43%), and the lambing rate was (57.14%, 100%, 71.43% and 85.71 %) for the four groups respectively (P<0.01).  Meanwhile, the fecundity rate for the same groups was (57.14%, 171.43%, 114.28% and 157.14%), respectively. Decreasing PMSG dose with Se supplementation appear to be a most appropriate program for induction of twinning and increasing of fertility and fecundity rates.