Objective:To investigate the effects of high fat diet and estrogen on cardiac structure and glucolipid metabolism. Methods:The rats were divided into 3 groups,the high-fat diet group,the ovariectomy and high-fat diet group and the ovariectomy and estrogen injection group. The change of body weight,visceral fat weight,blood glucose and blood insulin levels,serum estradiol and serum lipid levels were measured. Echocardiography was performed to evaluate the related indexes of cardiac structure. The histomorphological changes in hearts were observed under microscope by using hematoxylin-eosin (HE) staining. Results:Estrogen was negatively correlated with the degree of obesity;it can reduce fasting blood glucose and improve insulin resistance;it also decreased serum total cholesterol,protected myocardial cells by mitigating the degeneration and necrosis. Conclusion:Estrogen can effectively improve obesity-induced insulin resistance and abnormal lipid metabolism and protect heart structure.