Previous research has established that thought-action fusion contributes to the development and maintenance of obsessive–compulsive disorder (OCD), but the role of self-regulatory strategies as potential underlying mechanisms in this link has not been examined yet. This study carried out to examine the direct and indirect effects of thought-action fusion on OCD symptoms, with experiential avoidance, thought suppression, and depression acting as potential mediators. A clinical sample of OCD patients (n = 304; mean age = 31.69, SD = 8.48, females = 65.8%) was recruited for this study. Participants completed a series of self-report measures in a cross-sectional design. The results indicated that the effect of thought-action fusion on OCD symptoms was mediated by experiential avoidance and thought suppression. However, when depressive symptoms were included in the analysis, these factors alone no longer had a significant effect. Instead, the pathways of experiential avoidance and thought suppression associated with depressive symptoms mediated the link of thought-action fusion to OCD symptoms. This study emphasizes the importance of self-regulatory strategies, particularly in the manifestation of depressive symptoms, to link thought-action fusion to the OCD symptoms. Furthermore, this study offers further evidence in favor of the metacognitive model of OCD about the role of the meaning and power of intrusive thoughts, as dysfunctional metacognitive beliefs conceptualized as thought-action fusion, in OCD and adds new literature regarding self-regulatory strategies employed to address these dysfunctional metacognitive beliefs, particularly in the context of depression.