This study aimed to determine the psychometric properties of the Smartphone Addiction Scale (SAS) in a sample of 208 Iranians. The convenience sampling method was employed to select individuals with smartphones living in Tehran. The participants completed the SAS and Young’s Internet Addiction Test (IAT). Construct validity and convergence validity were employed to analyze the scale validity, whereas the retest method and Cronbach’s alpha were adopted to evaluate its reliability. According to the confirmatory factor analysis results of evaluating the construct validity and the SAS structure, the research data are consistent with the model. In other words, the fitting indices were within an appropriate range, and the SAS had a factor structure with six subscales. Therefore, the construct validity of the SAS was confirmed. Moreover, its convergence validity was confirmed with Young’s IAT (r= 0.75). The retest correlation coefficient (r= 0.93) and Cronbach’s alpha for internal consistency (α= 0.92) confirmed the reliability of the scale. Therefore, the 33-item SAS had acceptable psychometric properties in six scales. It can be used as a valid and reliable tool to analyze an Iranian population.