[Abstract] Objective To evaluate left ventricular diastolic function in patients with polycystic ovary syndrome by tissue Doppler imaging.Methods Routine echocardiographic examination of patients with polycystic ovarian syndrome (PCOS) with normal or low weight (group a), overweight or obesity (group B) due to infertility or irregular menstruation.And Record the data recording and image acquisition such as Peak e velocity in early diastole of two cusps(E), Ratio of maximum blood flow velocity (E) at the early stage of mitral valve diastole to maximum blood flow velocity (A) at late diastole (E/A), Early peak velocity of myocardial diastole in the left wall of tissue Doppler mitral annulus(Em), Late diastolic peak velocity(Am) etc. Both groups received venous blood in the early morning after 12 hours of fasting, Determination of blood lipid and blood glucose level by automatic biochemical instrument,Detection of serum insulin level by radioimmunoassay.Results Group B of Waist-to-hip ratio(WHR) and Insulin resistance index (HOMA-IR) is higher than group A. High density lipoprotein cholesterol(HDL-C)is Lower than group A. The difference is statistically significant(P<0.05). The difference of Cholesterol(TC), Triglyceride(TG) and Low density lipoprotein cholesterol (LDL-C) is not statistically significant(P＞0. 05). Group B of Em,Em/Am is higher than group A. E/Em is Lower than group A. The difference is statistically significant(P<0.05). The difference of Residual cardiac index is not statistically significant(P＞0. 05). Conclusion Left ventricular diastolic function decreased significantly in PCOS obese with insulin resistance (IR) . Evaluation of left ventricular diastolic function by tissue Doppler imaging is superior to the traditional method of evaluation of blood flow in bicuspid valve.