Background: Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS) is a urologic chronic pelvic pain syndrome with suboptimal treatment outcomes. Catastrophizing is an empirically supported risk factor for greater IC/BPS pain. Aims: In this study, a moderated multiple mediation model is tested in which several additional psychosocial risk factors (depression, illness and wellness-focused behavioral coping strategies) are proposed as mediators or moderators in the existing relationship between catastrophizing and IC/BPS pain. Design: The present questionnaire study employed a cross-sectional design. Settings and Participants: Female patients with an IC/BPS diagnosis (n = 341) were recruited at tertiary care sites. Methods: Participants completed questionnaires assessing pain, catastrophizing, behavioral coping strategies, and depressive symptoms. Aggregate factor scores were calculated following exploratory factor analyses. Results: It was found that patients with a greater tendency to catastrophize were more likely to engage in illness-focused coping strategies, which contributed to the reporting of greater sensory and affective pain. Furthermore, this mediating effect of illness-focused coping on affective pain was more likely to occur in those patients reporting greater depressive symptoms. Conclusions: Illness-focused behavioral coping is an important mechanism between maladaptive pain cognition and aspects of patient pain, with patients reporting greater depressive symptoms at increased risk for elevated pain. Patient management techniques, including screening for catastrophizing, coping, and depression, are recommended to enrich IC/BPS management.