Objective: Bariatric surgery is used more commonly than recent years among obesity treatment methods. The prevalence of eating disorders and its effect on surgical outcomes in bariatric surgery candidates are frequently discussed. The present study was planned to assess the prevalence of eating disorders in bariatric surgery candidates. Methods: A psychiatrist in routine proce-dure evaluated 108 bariatric surgery patients. Eating disorders diagnosis (binge eating disoder (BED), anorexia nervosa (AN), bulimia nervosa (BN)) were based to Diagnostic and Statistical Manual of Mental Disorders (DSM-5) and night eating syndrome (NES) diagnosis was based to Allison crieterias. Eating Attitudes Test (EAT) and Beck Depression Inventory (BDI) were administered to all participants. Results: The prevalence of any kind of eating disorder (BED, NES or both) was 23.1% (n=25). BED was 11.1% (n=12), NES 5.6% (n=6), both BED and NES 6.5% (n=7). We could not determine any patient with diagnose of AN or BN in our sample. There was no significant difference at Body Mass Index (BMI) between people with eating disorders and without eating disorders. The mean point of BDI score was 13.8 +/- 9.8. The 50% of sample had family history about psychiatric disease. 63.9% of the sample (n=69) had comorbid other medical conditions. Conclusion: Prevalence of eating disorders is substantially high in this group (23.1%). As we exactly not know the effect of eating disorders at surgery success and weight loss, it is important to determine the maladaptive eating behaviors at the beginning of surgery procedure.