Objective: To determine the prevalence of eating disorders (EDs) in women with polycystic ovary syndrome (PCOS) and the effects of EDs on health-related quality of life. Design: Cross-sectional study. Setting: University practice. Patient(s): Women with PCOS (Rotterdam criteria; n = 148) and controls seen for routine gynecologic care (n = 106) from 2015 to 2016. Intervention(s): Eating Disorder Examination-Questionnaire (EDE-Q), Night Eating Questionnaire (NEQ), Hospital Anxiety and Depression Scale, and Health-Related Quality of Life Questionnaire (PCOSQ). Main Outcome Measure(s): EDE-Q and NEQ scores, prevalence of bulimia nervosa (BN), binge eating disorder (BED), and night eating syndrome (NES). Result(s): Women with PCOS were at an increased risk for overall abnormal EDE-Q scores compared with controls (12.16% vs. 2.83%; odds ratio [OR], 4.75; 95% confidence interval [CI], 1.36, 16.58). Clinically significant elevated scores were noted for shape and weight concern. In unadjusted analysis, body mass index (OR, 1.06; 95% CI, 1.01, 1.11), elevated depression score (OR, 5.43; 95% CI, 1.85, 15.88), and elevated anxiety score (OR, 6.60; 95% CI, 2.45, 17.76) were associated with an abnormal EDE-Q global score. In the multivariable model, PCOS was associated with abnormal EDE-Q global score (adjusted OR, 4.67; 95% CI, 1.16, 18.80). Elevated EDE-Q scores inversely correlated with PCOSQ scores (r = -0.57). The prevalence of BN was 6.1%, of BED was 17.6%, and of NES was 12.9% in women with PCOS, with no differences compared with controls. Conclusion(s): Women with PCOS, especially those with concurrent anxiety symptoms but independent of obesity, have a significantly increased risk of abnormal EDE-Q scores. Our findings suggest the need for routine screening for ED in this population. (C) 2016 by American Society for Reproductive Medicine.