Aims: To assess the prevalence of catastrophizing in patients with temporomandibular disorders (TMD) and the possible associations between catastrophizing and treatment outcome. Methods: This review was registered in the Prospero database (CRD42018114233). Electronic searches were performed in PubMed, Scopus, and PsycINFO from the inception of each database up to October 26, 2018, and were combined with a hand search. Articles focusing on levels of catastrophizing and how catastrophizing affects pain levels and treatment outcomes for patients diagnosed with TMD were included, as well as studies reporting how treatment outcomes were affected by cognitive behavioral treatment as an addition to standard treatment for TMD. Reviews and case reports were excluded. Risk of bias was assessed with the Newcastle-Ottawa scale. Results: The literature search identified 266 articles. After screening of abstracts, the full texts of 59 articles were assessed. Of these, 37 articles, including 4,789 patients with TMD and 6,617 controls, met the inclusion criteria. Higher levels of pain catastrophizing were reported in patients with TMD, with a large effect size (Hedges' g = 0.86) compared to pain-free controls. Furthermore, associations of higher levels of catastrophizing with higher symptom severity and with poorer treatment outcome were reported together with indications of positive effects from cognitive behavioral therapy. Conclusion: The results suggest an association between catastrophizing and TMD that may affect not only symptom severity but also treatment outcome. Assessing levels of pain catastrophizing might therefore be valuable in the assessment and management of patients with TMD.