The influence of UV-light (240-390 nm) in dose 75.5-1510 J/m2 on the structural functional qualities (cytotoxic activity, antibody-produced ability, a level of expression of superficial receptors, a level cAMP) of lymphocytes peripheral blood of donors was investigated. Corregative action of UV-radiation on cytotoxic activity of lymphocytes in relation to cells of Ehrlich ascite carcinoma was revealed. The interrelation of modification types of plasmatic membrane components with a level of functional activity of lymphocytes was established. Was shown, that UV-light induces the decrease in a secondary level of messenger cAMP in cytosol of the photomodified cells. It is revealed, that UV-radiation causes stimulation of antibody-independent mechanism of cytotoxic lymphocytes, which is connected with activation of T-cells and with inhibition of antibody-dependent mechanism of cytotoxic activity.