Objective: The objective is to evaluate the prevalence and associated clinical characteristics of eating disorders (ED) in patients with obsessive-compulsive disorder (OCD). Method: This is a cross-sectional study comparing 815 patients with OCD. Participants were assessed with structured interviews and scales: SCID-I, Y-BOCS, (Int J Eat Disord 2010; 43:315-325) Dimensional Y-BOCS, BABS, Beck Depression and Anxiety Inventories. Results: Ninety-two patients (11.3%) presented the following EDs: binge-eating disorders [= 59 (7.2%)], bulimia nervosa [= 16 (2.0%)], or anorexia nervosa [= 17 (2.1%)]. Compared to OCD patients without ED (OCD-Non-ED), OCD-ED patients were more likely to be women with previous psychiatric treatment. Mean total scores in Y-BOCS, Dimensional Y-BOCS, and BABS were similar within groups. However, OCD-ED patients showed higher lifetime prevalence of comorbid conditions, higher anxiety and depression scores, and higher frequency of suicide attempts than did the OCD-Non-ED group. Primarily diagnosed OCD patients with comorbid ED may be associated with higher clinical severity. Discussion: Future longitudinal studies should investigate dimensional correlations between OCD and ED. © 2009 Wiley Periodicals, Inc.