Objective To oberseve the serum lipid and histopathology in ApoE gene knockout mice. Methods 24 ApoE gene knockout mice(bisexual each half) were selected,using 24 C57BL/6J mice as controls,to oberseve TC,LDL,HDL and the change of heart pathological morphology. Results The TC,LDL level of ApoE gene knockout mice were significantly higher than in control groups(P 0.05);the HDL level had no significantly difference in both groups;the area of atherosclerotic plaque of ApoE gene knockout mice was significantly higher than in control groups(P 0.05);there was clinical occurrence of atherosclerosisin ApoE gene knockout mice. Conclusion ApoE gene knockout mice promotes atherosclerosis easily.