Objective: To analyze the feasibility of triacylglycerol (TAG) as a surrogate marker for insulin resistance in Chinese women with polycystic ovary syndrome (PCOS). Methods: Height, weight, TAG, total cholesterol (TC), high density lipoprotein (HDL), OGTT, insulin release test were measured in 171 women with PCOS according to Rotterdam consensus, who went to Department of Obstetrics and Gynecology of Ruijin Hospital from May, 2012 to June, 2015. Body mass index (BMI) and HOMA-IR were calculated. PCOS patients were divided into obese and non-obese group by BMI to analyze the feasibility of TAG as a surrogate marker for insulin resistance in two groups. Results: TAG, HDL, TC, plasma glucose and insulin levels in obese group were significantly higher than those in non-obese group (P<0.05). The proportion of patients with insulin resistance was also higher in obese group (P=0.000). The ROC curve analysis demonstrated that TAG could not predict insulin resistance in obese group. But in non-obese group the areas under the ROC curve was 0.791. The optimal cut-off point was 1.585 mmol/L with sensitivity of 0.484 and specificity of 0.979. Conclusion: TAG can be used as a surrogate marker for insulin resistance in non-obese Chinese women with PCOS.