Objectives:It can be said that approximately 60-70% of the general population would probably experience at least one symptom of temporomandibular disorder (TMD) in their lives, but only about 5% of these people seek treatment. On the other hand, depression and anxiety are now recognized as a serious public health problem among adults. Anxiety disorder is a chronic, high-risk disease that may lead to dysfunction and reduce quality of life. The aim of this study was to assess the association between depression and anxiety with TMD in dentistry students of Zanjan Dental School in 2020-2021. Methods:The population of this study consisted of students with TMD, and the control population was selected from students of the same faculty. To collect the data, volunteers first answered questions about the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Then the Depression, Anxiety and Stress Scale (DASS-21) questionnaire was completed by students in both groups. The collected data were then entered into stata software version 14. Results:According to the results of univariate analysis of logistic regression, gender, tuition, residential status, stress, anxiety and depression have a significant effect on TMD (P <0.2). After examining the gisimultaneous effect of variables and eliminating possible confounding variables with multiple logistic regression models, stress was identified as the most effective factor in TMD (significance level in this model is less than 0.05). Conclusion:Based on findings, while there was a significant relationship between stress, depression and anxiety with symptoms of TMD, stress alone was identified as the most effective factor in developing TMD.