Effects of rhGM-CSF on reconstruction of hemopoietic function in mice exposed to total body gamma irradiation with a dose of 6.0Gy combined with 15% TBSA full thickness burn were further investigated. The result showed that hemopoietic function was damaged severely after the combined injury. There was a significant decrease of peripheral blood white cells, bone marrow mononuclear cells and CFU-GM. The lowest values occured at the initial period after injury. After administrating rhGM-CSF at 10µg/kg•d,-1, constinuously for 10 d,the significant increase of peripheral blood white cells was obsverved from day 11 to day 20 postinjury. The highest values could restored to pre-injury levels. Bone marrow mononuclear cells and CFU-GM also show a remarkable increase at day 10 and day 15 postinjury. All of these indicated that rhGM-CSF could stimulate hematopoietic progenitor cell to proliferate and differentiate,give support to recovery of hemopoietic function after combined radiation-burn injury at different levels.