Aim To establish a hyperlipidemia animal model and to study the immunologic injury and inflammtional mechanisms in the pathogenesis of hyperlipidemia.Methods 40 BALB/C mice were randomly divided into the hyperlipidemia group and normal control group.Hyperlipidemia group were fed with high-cholesterol diet(HCD);Control group were fed with normal diet.The changes of lipid metabolism and 5 kinds of Th1/Th2 cytokines were observed in two groups.Results Interleukin-2(IL-2),IL-4,IL-5,tumour-necrosis factor-α(TNF-α) and Interferon-γ(IFN-γ)were 3.75±0.07,6.16±0.55,18.70±4.61,57.97±6.57 and 6.17±0.76 ng/L in hyperlipidemia group.Compared with control group,the levels of total cholesterol(TC),triglyceride(TG),IL-5 and TNF-α were significantly higher in hyperlipidemia group(p<0.01).But no difference was noted in the levels of IFN-γ,IL-2 and IL-4(p>0.05).And there was obviously positive correlation between IL-5 and TNF-α(r=0.79,p<0.05).Conclusion Immunologic injury and inflammtional mechanisms played an important role in the occurrence and development of hyperlipidemia and atherosclerosis.