The experimental studies were conducted with Walker's carcinosarcoma n256 (from the U.S.A. bank), cancer of the mammary gland (RMK-1). Spontaneous –mice with mammary glands cancer (type B). The tasks were as follows: to study the effect of different doses LLLT on the growth of experimental tumors. Evaluation of the effectiveness by applying LLLT in combination with various chemotherapeutic agents (vincristin, 5-Fu, ciclophosphan). Research of LLLR effect on different types of tumors show that this treatment can be used for tumors-statistic effect and for increasing life-span in animals. Applying LLLR in combination with chemotherapeutic agents causes tumors-static action. The most effective combination was LLLT + vincristin which caused the inhibition of tumor growth in Walker's carcinosarcoma-by 92,87%, in RMK-1 - by 90,29% in comparing to controls. The combination of LLLT with HpD showed - the effect of laser therapy takes place in 30 min before the irradiation and is accompanied by a sharp reduction of the preparation's accumulation in the tumor cells.