Aims: The elderly population, both globally and in Iran, is increasing. The well-being of the elderly is a crucial aspect of health. This study aimed to examine the impact of social cognitive determinants on the healthy lifestyle of older adults. Instrument & Methods: This cross-sectional study was conducted in 2021, involving 455 elderly in Rasht City, Guilan Province. Data on demographic characteristics, lifestyle information, and constructs of the social cognitive theory were collected. Findings:The majority of participants had an average lifestyle. Among the various components, prevention received the highest score for a healthy lifestyle among the elderly, while physical activity received the lowest score. Among the constructs of the social cognitive theory, outcome expectancies had the highest mean score, while self-efficacy had the lowest mean score. The correlation analysis revealed significant and direct relationships between the constructs of the cognitive theory and healthy lifestyle scores among the elderly. Awareness, self-regulation, social support, and outcome expectations significantly predicted lifestyle behavior. Conclusion:The social cognitive theory holds predictive value for understanding the lifestyle of older adults.