Under study was the dynamics of functional properties of leukocytes of healthy people and patients after UV-irradiation of their blood, mixing the UV-irradiated and non-irradiated blood. It was shown that UV-irradiation and mixing the irradiated and non-irradiated blood facilitated the liberation of bactericidal cation proteins of leukocytes, higher expression of membrane receptors, growth factors, activation of reparation of DNA after its injury by gamma-rays. It proves the role of immediate activation of leukocytes of the circulating blood in trigger mechanisms of effects of autotransfusion of UV-irradiated blood.