Objective There have been several studies investigating the relationships between dysfunctional beliefs and obsessive-compulsive (OC) symptoms in obsessive-compulsive disorder (OCD). However, studies about the relationships between dysfunctional beliefs, especially thought-action fusion (TAF), and OC symptom dimensions have been scarce. Therefore, this study examined to what extent and how TAF subcomponents account for unique variability in four OC symptom dimensions. Methods Sixty-five patients with OCD and 45 healthy controls aged between 18 and 30 years completed measures for OC symptom dimensions, OC symptoms, and dysfunctional beliefs such as TAF, trait-guilt, and inflated responsibility. Results Three facets of TAF were exclusively associated with two symptom domains, namely, responsibility for harm and unacceptable thoughts, and explained the additional but small amount of variance to predict these two domains. In particular, the likelihood-others TAF positively predicted the unacceptable thoughts domain, whereas the likelihood-self TAF negatively predicted the aforementioned domain. For OC symptoms measured by the OC Inventory, no TAF components predicted the corresponding obsessing and mental neutralizing symptoms. Conclusion This study provides supporting evidence that the three TAF subcomponents may be differently associated with certain OC symptom dimensions, and a dimensional approach may complement typical symptom-oriented OC measures.