Previous research has highlighted the potential role of existential concerns (ECs) in Obsessive-Compulsive Disorder (OCD). However, empirical research has thus far only demonstrated the role of one existential issue in this disorder: namely, death anxiety. The present study explored the relationships between OCD symptoms and five ECs: Death anxiety, meaninglessness, isolation, identity, and guilt. In particular, the associations between these concerns and sexual and aggressive obsessions were examined. The sample consisted of 48 treatment-seeking individuals diagnosed with OCD. The results revealed that the five ECs were significantly associated with overall OCD severity. In addition, as hypothesised, death anxiety was significantly associated with aggressive obsessions, but not with sexual obsessions. Further, the ECs of identity, meaninglessness, and guilt were uniquely associated with sexual obsessions. The majority of these relationships remained significant after controlling for neuroticism. Clinical implications and directions for future research are discussed.