Current explanatory models for binge eating in binge eating disorder (BED) mostly rely on models for bulimia nervosa (BN), although research indicates different antecedents for binge eating in BED. This study investigates antecedents and maintaining factors in terms of positive mood, negative mood and tension in a sample of 22 women with BED using ecological momentary assessment over a 1-week. Values for negative mood were higher and those for positive mood lower during binge days compared with non-binge days. During binge days, negative mood and tension both strongly and significantly increased and positive mood strongly and significantly decreased at the first binge episode, followed by a slight though significant, and longer lasting decrease (negative mood, tension) or increase (positive mood) during a 4-h observation period following binge eating. Binge eating in BED seems to be triggered by an immediate breakdown of emotion regulation. There are no indications of an accumulation of negative mood triggering binge eating followed by immediate reinforcing mechanisms in terms of substantial and stable improvement of mood as observed in BN. These differences implicate a further specification of etiological models and could serve as a basis for developing new treatment approaches for BED.