The reproductive ability indicators of saiga female under conditions of semi-free dwelling in southern Ukraine were studied. It has been defined that activation of ovogenesis of saiga females begins in summer months (July-August) and is determined by the growth of a significant number of follicles. Maturation of follicles in adult females is observed in late autumn and in winter, that indicates their readiness to mate. Animal mating occurs in the short term within two or three weeks. The availability of pregnancy with enough simultaneous development of embryos and fetuses was surveyed in all females in winter-spring period. Activation of ovogenesis in young females begins later (October-November) than in adults, and is characterized by follicular development and oocytes’ maturation. Оnly a few well-developed females (up 20 %) reach puberty in 7–8-months, they become physiologically mature at 18–19 months of age. The indicators of reproductive females ability of Askanian saiga populations do not differ from similar parameters of this species of autochthonous populations. Some deviations in direction of terms of display of sexual activity are determined primarily by the climatic conditions and the availability of green fodder. The semi-free saiga dwelling at the large areas of Southern steppes and selective grazing of grasses promote normal functioning of all organs and systems, which ultimately determines its successful re-acclimatization.