Purpose: Post-event processing, defined by self-critical rumination following a stressful communication event, is significantly associated with reduced quality of life. However, despite its relevance to the stuttering experience, to date, only a few studies have investigated post-event processing among adults who stutter, and no study has identified clinical and psychosocial predictors of post-event processing. The purpose of this study was to determine the contributions of clinical markers of stuttering and psychosocial variables to post-event processing. Method: Adults who stutter (N = 96) participated in two virtual sessions. After completing the Trier Social Stress Test, a standardized social stress task in Session 1, participants completed measures of post-event processing, clinical markers of stuttering (i.e., the experience of stuttering, self- and observer-rated stuttering severity), and psychosocial characteristics (i.e., self-perceived performance, self-esteem, social anxiety, trait, and state self-compassion) in Session 2. Results: Hierarchical linear regression models indicated that a more negative experience of stuttering, higher self-rated stuttering severity, and greater social anxiety predicted more post-event processing. Greater self-perceived performance and state self-compassion predicted less rumination. Observer-rated severity, self-esteem, and trait self-compassion were not significantly associated with post-event processing behavior. Conclusion: Findings reveal clinical and psychosocial variables to consider in the assessment and mitigation of post-event processing behavior in adults who stutter, and to bolster resiliency to social stress.