Introduction: Self-efficacy refers to people’s belief in their ability to perform their duties efficiently in particular contexts and influences their choice of activities and situations. It determines how hard people will try and how long they will persist in the face of obstacles.

Method: The purpose of this study was to determine the validity and reliability of the Persian version of Task Self-Efficacy Scale for Everyday Activities )SEEA( (Robert, Dolansky, and Weber, 2010(. To this end, and to confirm the construct validity of the questionnaire, 425)207 male and 218 female( older adults at different levels of physical activity )Active, Inactive) were selected by random sampling and then completed the questionnaire. Using the translation-back translation method, the questionnaire was translated from English to Persian and from Persian to English by three sports psychologists and three English-language experts. The content and face validity of the Persian version of the questionnaire was confirmed by the three sports psychologists and the three English- language experts.

Results: Confirmatory Factor Analysis (CFA) based on structural equations was used for the validation of the structure of the questionnaire. Cronbach alpha coefficient was used to validate the internal consistency of the questionnaire, and intra-class correlation coefficient under test-retest method with 4-weeks interval was used to study the temporal reliability of the items. The results showed that SEEA had an acceptable fit index (RMSEA = 0.055, CFI = 1.00., TLI = 0.99), internal consistency (Self-care = 0.987, Mobility = 0.986, and the total = 0.987), and temporal reliability (Self-care = 0.74, Mobility= 0.82, and the total = 0.83).

Conclusion: These findings indicated good validity and reliability for the Persian version of Self-Efficacy Scale for Everyday Activities for older adults. Therefore, the Persian version of the questionnaire can be employed as a tool to study and evaluate the self-efficacy of Iranian older adult.