The search for ideal protective agents for use in radiotherapy or post-exposure treatment of victims of radiation accidents is one of the actual problems of radiation protection. Laser irradiation device for the protection of biological objects from the action of ionizing radiation to be used in practice has been manufactured (invention patent RU 2 428 228 C2). This device is used to study the action of various doses of laser radiation and combined irradiation with laser and gamma-radiation, on peripheral blood parameters and number of bone marrow karyocytes of the experimental mice line C57ВL/6. The mice were irradiated with ionizing and laser radiation, separately one by one in a special bench. The time interval between two types of irradiation did not exceed 30 min. First, the mice were exposed to γ-radiation then to laser radiation. It was shown that laser radiation can be applied to improve the recovery of hematogenesis after the action of ionizing radiation on biological objects. Then, experiments were conducted to study the action of γrays and the combined action of laser radiation and γ -rays on survival, weight and skin of experimental mice. The authors investigated also the action of gamma-rays and combined effects of 650 nm laser radiation and gamma-rays on general mitotic index of bone marrow cells of mice. The method of the laser radiation-protection of biological objects contributes to an increase in the viability of mice, prevents the damages of skin and also increases the mitotic activity of mice bone marrow cells.