Abstract Study question Is an increased association of eating disorders (ED) in women with polycystic ovary syndrome (PCOS) than in women without PCOS? Summary answer Women with PCOS have an increased association of ED than women without PCOS. What is known already PCOS is one of the most common endocrinopathies in women. It has been reported to be associated with psychological distress and dissatisfaction with self-appearance due to clinical features of the syndrome, such as hyperandrogenism, metabolic disorders, obesity, and infertility, leading to lower self-esteem and an increased risk of developing ED. This association presents a clinical dilemma, as the primary treatment for PCOS emphasizes the importance of weight loss, leading to potential distress in patients and worsening ED behaviors. Study design, size, duration This was a cross-sectional study. The sample size was calculated with the formula for comparison of proportions in two independent groups, with a confidence level of 95% and power of 80%, obtaining a minimum sample size of 116 participants per group. We included a total of 643 women between July to August 2022. Participants/materials, setting, methods 643 women who attended a gynecological consultation in Murcia, Spain were included, 238 with PCOS and 450 controls. The information was collected online. The score of the EDE-Q questionnaire and the clinical epidemiological characteristics were compared between the groups. Pearson Chi-square was used for categorical variables, and Mann Whitney U test for quantitative variables. Statistical significance was considered with a P-value <0.05. The data were analyzed with the SPSS version 20. Main results and the role of chance We found an increased risk of presenting ED in women with PCOS than in women not reporting PCOS (27% vs 13.7%). The odds of presenting an abnormal EDE-Q score (>4) were greater in women with PCOS (odds ratio [OR] 2.325, 95% confidence interval [CI], 1.55, 3.47, P < 0.001) than in women without PCOS. Clinically significant elevated scores were observed in the PCOS group for all four subscales of ED, but with a more significant impact on the eating concern scale (OR 2.49, 95% CI, 1.47, 4.21, P < 0.001). We found more prevalence of binge episodes in the PCOS group (OR 1.8, 95% IC, 1.3, 2.5, P < 0.001). When evaluating the characteristic of women with diagnosis of PCOS, we observed a higher body mass index (30.4 vs 23.4 [95% CI, 0.89-1.4, P < 0.001]) and more prevalence of amenorrhea (100% vs 87%, P < 0.001) in women with ED diagnosis than in women without ED. Limitations, reasons for caution The limitations observed in our study were that the information was based on an online questionnaire, so there is a possible reporting bias or misunderstanding of the questions. Wider implications of the findings The present study shows that women with diagnosis of PCOS have an increased risk of presenting ED than women without PCOS. This is more prevalent in women with a longer period of amenorrhea and a higher body mass index. Trial registration number Not applicable