The purpose of this study was to determine the factors affecting the ac-ceptance of Picture Archiving and Communication System (PACS) by healthcare professionals based on the Unified Theory of Acceptance and Use of Technology (UTAUT). A total of 600 nurses, physicians, and paramedical staffs who perform their main tasks using the PACS in educational hospitals of Mazandaran University of Medical Sciences were participated in the study. Construct validity and internal reliability were tested by employing a confirmatory factor analysis (CFA) and a reliability analysis, respectively. Further, structural equation modeling (SEM) was employed to test hypothe-sized relationships. The results indicated that Performance Expectancy, Ef-fort Expectancy, and Social Influence had a direct effect on Behavioral In-tention. Whereas Facilitating Condition and Behavioral Intention had a di-rect effect on Use Behavior.