The effect of hot water extract of Sophora japonica Linne (Koehwa) flower on lipid content were studied in terms of hematological variables in rats fed with high fat diet. Experimental rats were divided into basal diet only (BDG), high fat diet control (FDC), high fat diet and 6% Sophora japonica extract powder (FD6S), and high fat diet and 12% Sophora japonica extract powder (FD12S) groups. The levels of hematological variables were not significantly different among the four groups, whereas transferrin concentration and glutamic oxaloacetate transaminase (GOT) activity in serum metabolic variables were significantly different. Transferrin concentration was higher in the FD6S and FD12S groups than in BDG and FDC groups. FD6S and FD12S groups showed significantly lower level of GOT activity. Total cholesterol levels of FD6S and FD12S groups were 220.38 and 205.02 mg/dL in the serum, respectively. Total cholesterol levels of FD6S and FD12S groups were lower than that of FDC group (341.38 mg/dL) and the same level as that of FDG group (216.18 mg/dL). HDL- and LDL-cholesterol levels of FDC group were 26.84 and 62.91 mg/dL, whereas those of FD12S group were 38.02 and 44.16 mg/dL. Supplementation of 12% Koehwa extract powder remarkably increased HDL-cholesterol level and greatly decreased LDL-cholesterol level. Atherogenic indices in FD6S and FD12S groups were significantly lower than those of yje FDG group. The FD12S group supplemented with Koehwa extract showed lower triglyceride concentration than that of the FDC group. These results suggested that dietary supplementation of Koehwa extracts did not have any adversary effect on the hematological variables, but improved the lipid content and reduced hepatic damage of the high fat fed rats.