Obsessive-compulsive disorder (OCD) is one of the most debilitating health conditions in the world. There has been a vast amount of research into factors that increase the likelihood of developing OCD, and there are several explanatory models. Current cognitive models of OCD can be split into appraisal-based and self-doubt models. To date, cognitive-behavioural therapy for OCD (grounded in appraisal-based models) is the recommended treatment approach, and research into the importance of self-doubt beliefs has been somewhat neglected. This paper therefore aims to consolidate current research, utilizing a systematic review approach, to establish the relationship between fear of self, self-ambivalence, and obsessive-compulsive symptomatology. A systematic search was conducted based on inclusion criteria identified for this review. Papers were then individually appraised for quality and key data extracted from each paper. A total of 11 studies were included in the final sample. Fear of self and self-ambivalence were both consistently found to be significant predictors of obsessive-compulsive symptomatology. In particular, research suggests that there is a strong link between self-doubt beliefs and obsessions and obsessional beliefs related to OCD. Limitations of the review and suggestions for future research are made and applications to clinical practice discussed.