While fear and anger have been extensively studied as emotions involved in posttraumatic stress disorder, shame is an important emotion to examine in those who have experienced a traumatic event, as it is often associated with treatment avoidance and treatment resistance. Compared to guilt, which is associated with having participated in something that violates social/cultural norms or expectations, shame is associated with a negative perception of the self. The current paper sought to examine the role of shame proneness and guilt proneness, as it relates to posttraumatic cognitions and posttraumatic stress symptoms (PTSS) among women reporting a history of sexual trauma. Seventy-two community-recruited women with a history of sexual trauma completed self-report measures of shame and guilt proneness and negative posttraumatic cognitions as well as a semi-structured interview assessing PTSS. There was an indirect effect of shame proneness on PTSS, through its positive association with negative cognitions about the self but not others or the world. Guilt proneness was not significantly related to PTSS or negative posttraumatic cognitions. The current paper outlines the importance of these findings and future directions for continuing to better understand the relations between shame and posttraumatic stress disorder symptoms and treatment.