For decades, it has been suggested that people with cluster B personality disorders experience difficulties in social cognition. However, empirical findings related to this idea have been mixed and inconsistent. The aim of the present study was to systematize the existing findings on the relationship between empathy, the attribution of mental states, and Cluster B personality disorders in adults. A systematic review was carried out following the PRISMA protocol and using the Scopus and PubMed databases. Twenty-two studies were selected. The results reveal that, for borderline personality disorder, there are contradictory outcomes regarding its association with empathy and the attribution of mental states. Narcissistic personality disorder was associated with alterations in both socio-cognitive processes. Antisocial personality disorder was related to difficulties in emotional recognition, although its relationship with empathy and the attribution of mental states is not clear. Histrionic personality disorder presented difficulties in emotional recognition and in Theory of Mind. Future research should clarify these differences and better understand the socio-cognitive processes in individuals with personality disorders.