Self-perceptions of moral deficiencies have previously been linked with obsessive- compulsive phenomena. However, beliefs about the nature of morality and character may determine how such deficiencies are perceived and handled. The current research examined the extent to which implicit perceptions about the stability of morality and character (entity theory of morality and character) are associated with OC symptoms in a nonclinical sample. For this purpose, we combined several existing implicit theories scales into a single measure of entity theory of morality and character (Study 1), and examined the hypotheses that holding an entity theory of morality and character is associated with obsessive-compulsive symptoms and that this association is mediated by obsessive-compulsive related beliefs (Study 2). Findings suggest that belief in the over-importance of thoughts and in the importance of controlling one's thoughts, an inflated sense of responsibility, and threat overestimation are reliable mediators of the relationship between entity theory of morality and obsessive-compulsive symptoms. Implications of these findings for theory and treatment of OCD are discussed.