Aims: To use the Symptom Checklist-90-Revised (SCL-90-R)-based instruments of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and the Primary Care Evaluation of Mental Disorders (PRIME-MD)- based instruments of the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) in order to compare these Axis II scores in temporomandibular disorder (TMD) patients. Methods: Demographic and socioeconomic data, Axis I diagnoses, and Axis II evaluations (depression, nonspecific physical symptoms, anxiety, and Graded Chronic Pain Scale [GCPS]) were compared between two groups of patients-142 TMD patients diagnosed according to the RDC/TMD (RDC group) and 157 TMD patients diagnosed according to the DC/TMD (DC group). Pearson's chi-square test, Fisher's exact test, and Mann-Whitney test were used, and P values were adjusted for multiple comparisons. Results: The prevalences of severe depression, nonspecific physical symptoms, and anxiety were significantly lower in the DC group than in the RDC group, with no differences between groups for Axis I diagnoses, characteristic pain intensity (CPI), or GCPS. Conclusion: Within the limitations of this study, the present findings reveal differences in the presence of severe depression, nonspecific physical symptoms, and anxiety between the RDC and DC groups. The differences may reflect the cut-off scores of the SCL-90-R and the PRIME-MD tools. Keywords: Axis II, Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), Primary Care Evaluation of Mental Disorders (PRIME-MD), Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), Symptom Checklist-90-Revised (SCL-90-R)