Objectives: This study was conducted to assess the psychometric properties of the Persian version of the overall anxiety severity and impairment scale (OASIS), a measure designed to evaluate the severity and functional impairments associated with clinical and subsyndromal anxiety. Methods: Using a descriptive-analytic framework, first, the OASIS was translated into Persian according to the forward-backward translation guidelines. Then, a total of 463 students of Guilan University of Medical Sciences in the academic year 2017 - 18 were selected using the convenience sampling method. Participants completed seven measures (i.e., OASIS, anxiety and stress subscales of depression anxiety stress scales-21, Beck anxiety inventory, openness subscale of NEO five-factor inventory, positive affect and negative affect scales, Connor-Davidson resilience scale, and state subscale of state-trait anxiety inventory), and the data were analyzed by SPSS V. 20.0 for windows and Lisrel V. 8.80. Results: Internal consistency reliability of the OASIS was acceptable (Cronbach’s $α$ = 0.877). The exploratory factor analysis indicated that all items were loaded on a single factor (loadings = 0.799 - 0.849). The confirmatory factor analysis revealed that the single-factor model has resulted in an adequate model fit. The OASIS was positively correlated with the anxiety- and negative affect-related scales, whereas it was negatively correlated with the resilience- and positive affect-related scales. Correlations with the openness subscale were not significant. Conclusions: In line with previous studies, the findings showed that the psychometric properties of the Persian version of the OASIS are acceptable. Therefore, it seems that the measure can be used in clinical practices and research studies in Iran.