The experiment presents the data on the effects of low doses of gamma radiation on productivity and hematological parameters of peripheral blood of sheep of Prekos breed. The total gamma-irradiation was carried out for gamma-setting “Puma” with a radiation source Cs-137 for irradiating the exposure dose 0,28 · 10–4 A/kg (6,40–6,57 R/min). It was found that low doses of ionizing radiation, in the exposure doses range of 0,65 · 10–2 C/kg – 2,58 · 10–2 C/kg, stimulate the growth of young sheep, which manifests itself in excess body weight of the experimental animals in comparison with the biological control for 6–9 %, and in increase of wool productivity of 3,6–8 %. The technical quality of the wool in fineness, length, crimp, suint content did not differ from the wool of sheep from biological control. The experimental animals had a slight dose-dependent decrease in the number of leukocytes, including lymphocytes and neutrophils. This reduction was 40–50 % of baseline during the gamma irradiation at a dose of 75 and 100 F for 5–10 days after exposure to radiation, and 15–25 % of baseline at a dose of 25 and 50 R. 30–60 day of the study showed stabilization of both the total number of leukocytes and violation in the ratio of lymphocytes and neutrophils in the direction of increasing the content of the first, and the reduction in the relative number of neutrophils. In the same period there was a shift of neutrophil formula to the left in leukogram. Myeloid and young forms of neutrophils started to appear. All this indicates the recovery of leukopoiesis in red bone marrow. The experimental group of sheep did not have changes of erythropoiesis. The number of red blood cells and hemoglobin level in the experimental groups matched indicators of biological controls. Thus, the effect of low doses of ionizing radiation on sheep provokes the phenomenon of radiation hormesis, manifested by stimulation of physiological processes, by increase in meat and wool productivity, by increasing immunobiological reactivity.