OBJECTIVE： To study the improvement effects of Shenshao yiqi yangxue granule on experimental aplastic anemia （AA） in mice and the preventive and therapeutic effects of it on myelosuppressive in mice. METHODS： Totally 72 mice were randomly divided into blank group （normal saline）， model group （normal saline）， positive control group （Yixuesheng capsule， 0.625 g/kg in content）， Shenshao yiqi yangxue granule low-dose， medium-dose and high-dose groups （1.26， 7.56， 15.12 g/kg by crude drug）， with 12 mice in each group. Except for blank group， other groups were given 60Co-γ irradiation combined with intraperitoneal injection of CTX to induce AA model. After modeling， they were given relevant medicine intragastrically once a day， for consecutive 7 d. After 6 days of administration， the mice were placed on a treadmill for exhaustion test， and the exhaustion distance and exhaustion time were measured. After 7 days of administration， the changes of peripheral blood （the number of RBC， WBC， PLT and content of HGB） were determined of mice in each group. The percentage of reticulocyte （Ret） was measured after blood smear， and the number of bone marrow nucleated cells （BMNC） was determined after bone marrow smear. Another 90 mice were collected， grouped and given relevant medicine as above， with 15 mice in each group. They were relevant medicine intragastrically once a day， for consecutive 12 d. After 3 days of administration， except for blank group， other groups were given 5-fluorouracil intraperitoneally to induce the bone marrow suppression model at the beginning of medication. After medication， peripheral hemogram， Ret and the number of BMNC were determined in each group. RESULTS： Compared with blank group， the exhaustion distance and exhaustion time of AA model group were significantly decreased （P＜0.01）， while the number of RBC， WBC， PLT and content of HGB， Ret and the number of BMNC were decreased significantly （P＜0.05 or P＜0.01）. Compared with model group， the exhaustion distance and exhaustion time of positive control group and Shenshao yiqi yangxue granule medium-dose and high-dose groups were increased significantly （P＜0.05 or P＜0.01）； the peripheral hemogram indicators， Ret and the number of BMNC were increased significantly in positive control group and Shenshao yiqi yangxue granule high-dose group， and Ret of Shenshao yiqi yangxue granule medium-dose group was increased significantly （P＜0.05 or P＜0.01）. In bone marrow suppression model， compared with blank group， the number of WBC， RBC and PLT， Ret， the number of BMNC were decreased significantly in model group （P＜0.05 or P＜0.01）. Compared with model group， the number of WBC， RBC and PLT， Ret and the number of BMNC in peripheral blood were increased significantly in positive control group and Shenshao yiqi yangxue granule high-dose group， and the number of RBC， Ret and the number of BMNC were increased significantly in Shenshao yiqi yangxue granule medium-dose group （P＜0.05 or P＜0.01）. CONCLUSIONS： Shenshao yiqi yangxue granule has certain improvement effects on AA in mice， and can prevent and treat myelosuppression in mice.