Aims: To examine whether catastrophizing is associated with clinical examination findings, pain-related activity interference, and health care use among patients with pain related to temporomandibular disorders (TMD). Methods: Patients with TMD (n = 338; 87% female; mean age, 37 years) completed measures of pain, pain-related activity interference, health care use, and depression, and received a Research Diagnostic Criteria/ Temporomandibular Disorders (RDC/TMD) clinical examination from an oral medicine specialist. Results: Catastrophizing was not significantly associated with the more objective clinical examination measures of maximum assisted jaw opening and jaw-joint sounds, but it was associated with the more subjective examination measures (unassisted opening without pain, extraoral muscle site palpation pain severity, joint site palpation pain severity) and with increased TMD-related activity interference and number of health care visits (P values for all .01). Even after controlling for demographic variables, pain duration, and depression severity, catastrophizing remained significantly associated with extraoral muscle and joint site palpation pain severity and with activity interference and number of health care visits. Conclusion: TMD patients who catastrophize have higher scores on clinical examination measures reflecting more widely dispersed and severe pain upon palpation of TMD-related facial muscle and joint sites, as well as greater TMD-related activity interference and health care use. Clinicians should consider screening patients with moderate or greater TMD pain and activity interference for catastrophizing. Cognitive-behavioral interventions may help reduce pain, disability, and health care use of patients who catastrophize. Keywords: activity interference, catastrophizing, chronic pain, Reasearch Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), temporomandibular disorders