© 2018 by Turkish Association of Neuropsychiatry.Introduction: Poor adherence is widely observed in MS as in other chronic diseases; therefore, improving adherence should be a significant treatment objective. Therefore, it is important to determine the causes of nonadherence and to make improvement plans by establishing a special measurement tool for MS patients. The aim of this study is to investigate validity and Turkish equivalence of The Multiple Sclerosis Treatment Adherence Questionnaire (MS-TAQ) that developed by Paul Wicks and Michael Massagli in 2009. Methods: The sample of the methodological study comprised 198 MS patients who stayed in University Faculty of Medicine, Department of Neurology, MS clinic between July 2016 and February 2017. In the research, “Data Collection Form” and “MS-TAQ” was used. To conduct this study, permission was obtained from the university ethics committee and the hospital administration. All participants in the study were informed of the study’s purpose and their role. Results: Translation procedure (forward and backward) and pre-test were performed for translation equivalence and linguistic adaptation. MS-TAQ’s Cronbach alfa coefficient 0.83 were calculated. According to expert’s suggestion modifications was made and content validity index was calculated with Davis technic between 1.0–1.4. Conclusion: As a result, “MS-TAQ” has been found a sufficiently valid and reliable tool in Turkey.