Purpose: The purpose of this study was to investigate the moderating effect of chronic job discrimination on the relationships among job demands, job resources, personal resources and psychological well-being among aged workers. Design/methodology/approach: This study used "National Survey of Midlife Development in the United States (MIDUS Refresher)" data collected from 862 aged workers in the United States from 2011-2014. A moderated multiple regression analysis was adopted. Findings: The results of the multiple regression analysis show that skill discretion, self-esteem, optimism and active coping had positive effects on psychological well-being, while chronic job discrimination had a negative effect on psychological well-being. Co-worker support, supervisor support, job demands and decision-making authority were not significant. Among the interaction terms, the moderating effect between optimism and chronic job discrimination was significant. Originality/value: Based on the results, this study offers implications for understanding the effects of job discrimination in the workplace among aged workers and their perceived psychological well-being, in the context of job demands and resources (JD-R) model.