〔Abstract〕 Objective To investigate the relationship between the level of the human chorionic gonadotropin(hCG) 14 days after frozen embryo transfer and pregnancy outcomes in polycystic ovary syndrome(PCOS) and its related factors. Methods 607 PCOS patients and 1636 controls were analyzed retrospectively in our hospital.The baseline data,hCG level 14 days after frozen embryo transfer and pregnancy outcomes were compared between the two groups.The predictive value of hCG level 14 days after embryo transfer on the live birth of PCOS patients and its related factors were analyzed. Results Compared with the control group,the level of hCG 14 days after frozen embryo transfer in PCOS group decreased,and the live birth rate decreased(P<0.05).The level of hCG 14 days after frozen embryo transfer was an independent predictor of live birth in PCOS patients.The area under the ROC curve(AUC) was 0.903,95%CI=0.878-0.928(P<0.001),the cut-off value was 1 634.25 IU/L with a 74.6% sensitivity and a 88.5% specificity.BMI was negatively correlated with hCG level(P<0.001). Conclusion The level of hCG 14 days after frozen embryo transfer in PCOS patients is low,which is an independent predictor of live birth in PCOS patients and has a high predictive value.hCG level is negatively correlated with BMI.