This study was designed to document eating disorder symptoms in a well-defined sample of patients with bipolar disorder and to evaluate the relationship of current loss of control over eating (LOC) to demographic and clinical features hypothesized to characterize bipolar patients at risk for disordered eating. Eighty-one patients enrolled in the Bipolar Disorder Center for Pennsylvanians provided demographic information and completed the Structured Clinical Interview for DSM-IV Axis I Disorders. The Eating Disorder Examination was administered by independent clinicians to evaluate current and lifetime eating disorder symptomatology. Twenty-one percent of participants met DSM-IV criteria for a lifetime eating disorder, and 44% reported a history of LOC. Patients who endorsed weekly LOC during the past six months (n=18) were heavier, had more atypical depressive symptoms, and were more likely to have a lifetime substance use disorder compared to patients in the rest of the sample (n=63). These findings indicate that eating disorder symptoms are prevalent in patients with bipolar disorder and are associated with obesity and other psychiatric morbidity. Screening for eating disorders in bipolar patients is warranted, as intervention may minimize distress and improve treatment outcome.