Background: TMDs are one of the most common reasons for pain and discomfort in the orofacial region including ears and forehead. They are multifactorial conditions which may be caused due to genetic factors, stress, or malocclusion. Objectives: the aim of the present study was to assess the knowledge level of dental students and dental interns about TMJ disorders. Subjects and methods: This cross-sectional study was conducted on a sample of 512 dental students; undergraduates (level 10, 11, and 12) and dental interns. Representative samples were collected from different governmental and private dental colleges in KSA. A questionnaire of 10 items was created on Google forms and distributed to the dental students. Results: from the 10 knowledge questions only two questions were correctly recorded by more than 50% of the participants, there were no significant differences between private and governmental, male and female as well as among different academic levels for all questions regarding Knowledge about TMDs. Also, there were no association between knowledge level and gender or academic levels of the participants, but college type was positively associated with knowledge level of the students. Conclusion: Knowledge level about TMDs was insufficient among undergraduates and dental intern students, and the mean knowledge score was roughly increased by increasing students' academic years. Also, college type governmental or private was significant associated with students' knowledge level.