The aim of this study was to develop a scale to measure the attitudes of the university academic and administrative staff and students toward sexual harassment and assault, and examine its psychometric properties. After the development of the item pool and examination of the content validity of the intended items, Exploratory Factor Analysis (EFA) and parallel analysis was conducted and Cronbach's alpha reliability coefficient was calculated collecting data from 150 participants (54.7% of female and 45.3% of male) for the initial version (comprised of 12 items) of the Attitudes Toward Sexual Harassment and Assault Scale (ATSHAS). In the second phase, Confirmatory Factor Analysis (CFA) was conducted with 354 participants (54% of female and 46% of male) for the revised version (10 items) of the ATSHAS. Additionally, Cronbach's alpha reliability coefficient was calculated with second sample. After developing the item pool, the completion of the first phase of the study took 5 months, and the second phase took 4 months. The final version of the ATSHAS consisting of nine items demonstrated sufficient psychometric properties for measuring attitudes toward sexual harassment and assault in the university environment.