Ecological momentary assessment (EMA) data suggest that global negative affect (NA) increases prior to and decreases following episodes of binge eating and purging, providing support for the affect regulation model of BN. The current study examined whether facets of NA are differentially related to bulimic behaviors. Women with bulimia nervosa (BN; n = 133) completed a 2-week EMA protocol. Momentary assessments of 4 facets of NA (Fear, Guilt, Hostility, and Sadness) were derived from the PANAS subscales. Trajectories of the NA facets were modeled prior to and following binge-only, purge-only, and binge/purge events. Fear, Guilt, Hostility, and Sadness increased prior to and decreased following binge-only and binge/purge events. The same results were found for purge-only events, with the exception that Hostility did not increase significantly prior to purging. Notably, ratings of Guilt were higher than those of Fear, Hostility, and Sadness at the time of binge-only and binge/purge events. Furthermore, post hoc analyses demonstrate that Guilt increased prior to and decreased following the 3 behavior types, even after controlling for Fear, Hostility, and Sadness. These results provide further support for the affect regulation model of BN and also suggest that guilt may be particularly important to the pathology of BN.