To evaluate the sleep electroencephalogram (EEG) characteristics of bulimia, all-night sleep EEGs were performed on 11 women meeting DSM-III criteria for bulimia. Comparison groups consisted of young women outpatients with major depression (n = 44) and young normal women (n = 20). The sleep EEGs of the bulimic patients were largely indistinguishable from those of the normal controls, except for a trend toward increased rapid eye movement (REM) density in the first REM period among the bulimic subjects. No differences in any sleep EEG measure were observed between bulimic patients with major depression and those without affective disorder. By contrast, the outpatients with major depression displayed marked sleep continuity disturbances, as well as significantly increased REM intensity and REM density, as compared to normal controls. Implications of these results with respect to the hypothesis that bulimia is related to major affective disorder are discussed.