Work volition refers to the perceived ability of an individual to choose work under constraints. As they age, older workers often face declines in cognitive functioning and adaptability, as well as age discrimination in organizations. Our goal was to examine the relation between the mentioned constraints and work volition for aging workers, and whether general self-efficacy moderated the associations between constraints and work volition. A total of 350 working Chinese (aged over 45 years) in Hong Kong were recruited. Structural equation modeling (SEM) result showed that perceived age discrimination and cognitive constraint (planning and organization) were salient correlations of work volition. Multi-sample SEM analysis verified that general self-efficacy moderated the association between the cognitive constraints as well as perceived age discrimination in the workplace and work volition. Limitations and recommendations, including assessment of work volition, strengthening of general self-efficacy, and elimination of age discrimination, were discussed.