Background and Objective: Work-related musculoskeletal disorders (MSDs) are highly common and considered as the main factor leading to lost work time, increased costs, and hazards of manual labour work. Dentists are predisposed to work-related MSDs due to their job and methods of service delivery. Surveys have indicated that ergonomic design of job equipment and environment, proper posture, regular rest breaks and stretching exercises between patients can positively effect on the musculoskeletal system of dentists, reducing work-related musculoskeletal disorders. The aim of the present study was to evaluate the effect of educational intervention on musculoskeletal disorders in dentists who work in private dental clinics in Tehran, Iran during 2016. Materials and Methods: This study was carried out on 84 dentists working in private dental clinics in Tehran using before-after method. The data were gathered using demographic characteristics questionnaire and standardized Cornell Musculoskeletal Discomfort Questionnaire (CMDQ). Educational intervention was implemented distributing educational pamphlets among all participants. Data were re-measured 2 months after educational intervention using CMDQ. Data and changes in them were tested before and after educational intervention using SPSS 22 Software, Wilcoxon Signed Rank Test, McNemar test, and Linear Regression test.