This study was carried out to investigate the inhibiting and repairing effects of Bojung-ikki-tang Gamibang(BI-G) on the bone marrow injuries in rats. Bone marrow injury was induced by a single intraperitoneal injection of cyclophosphamide(CP)(150mg/kg). In experiment I, designed for inhibiting effect, extract of BI-G(80mg) was administrated from pre-5 days to post-5 days of CP injection. In experiment II, designed for repairing effect, extract of BI-G(80mg) was administrated after 5 days to 12 days of CP injection. Hematological and histopathological examinations were performed at 5 days after CP injection in experiment I, and at 12 days after CP injection in experiment II. In experiment I, the results were as follows ; RBC(${ imes}10^6/{mu}l$) of BI-G treated group$(8.39{pm}0.84)$ was increased significantly compared with control group$(7.52{pm}7.67)$. Hemoglobin(g/dl) of BI-G treated group$(13.76{pm}1.20)$ was increased significantly compared with control group$(12.24{pm}1.11)$. WBC(${ imes}10^3/{mu}l$) of BI-G treated group$(1.75{pm}0.41)$ was increased significantly compared with control group$(0.55{pm}0.17)$. Necrotic changes of myeloid cells of BI-G treated group were less severe than those of control group. Histopathologically, distention of sinus and edematous changes of bone marrow of BI-G treated group were alleviated compared with those of control group. In experiment II, the results were as follows ; WBC(${ imes}10^3/{mu}l$) of BI-G treated group(4.27 0.94) was increased significantly compared with control group$(3.02{pm}0.79)$. Hemoglobin(g/dl) of BI-G treated group$(12.61{pm}0.85)$ was increased significantly compared with control group$(11.49{pm}0.74)$. Platelets(${ imes}10^3/{mu}l$) of BI-G treated group$(1885{pm}133)$ was increased significantly compared with control group$(1616{pm}251)$. These results indicated that Bojung-ikki-tang Gamibang has the inhibiting and repairing effects on the cyclophosphamide-induced bone marrow injuries in rats.