The present study aimed to compare the psychometric properties of the Cognitive Acceptance Questionnaire developed by Cromer and Rose (2016) based on the Graded Response Item Response Theory model, and to propose a structural equation model of cognitive acceptance based on psychological flexibility, personality traits, and curiosity among male and female students of Islamic Azad University, Bandar Abbas Branch. Using cluster sampling, 491 participants were selected for analyzing the psychometric properties of the Cognitive Acceptance Questionnaire, and 581 participants were chosen for the structural equation modeling. Data were collected using the Cognitive Acceptance Questionnaire by Cromer and Rose (2016), the Psychological Flexibility Questionnaire by Ben Itzhak et al. (2014), the 60-item short form of the NEO Personality Inventory, and the Curiosity and Exploration Inventory by Kashdan et al. (2009).The results of the first study indicated that, based on the Waltz and Basel method, the content validity ratio and the content validity index of the Cognitive Acceptance Questionnaire were satisfactory. According to classical test theory and the graded response item response theory, the item parameters were acceptable. The factor loadings of the questionnaire items were desirable, and the test information function peaked around the average theta level.