The goal of the present study was to investigate the influence of expressive suppression and cognitive reappraisal on eating-related symptomatology in anorexia nervosa (AN) and bulimia nervosa (BN). Secondly, on the background of theoretical models proposing a reciprocal relationship between suppression and rumination, we sought to understand whether inhibition of emotional expression also affects ruminative thinking in eating disorders. Women with AN (n = 39), BN (n = 37) and a control group (CG, n = 41) were randomly assigned to either engage in suppression or reappraisal during a sadness-eliciting film clip. Levels of drive to eat, anticipated loss of control over eating and ruminative thoughts were rated before and after the induction of emotion regulation. Induced expressive suppression led to a decrease of reported drive to eat in AN and an increase of anticipated loss of control over eating in BN. All groups responded to suppression with greater rumination, whereas no significant changes were found for reappraisal. Mediation analyses on trait questionnaires pointed to rumination as a partial mediator of the correlation between suppression and eating disorder pathology. Results are discussed in line with recent empirical research and current emotion regulation theories.