This study aimed to elucidate how career adaptability (CA) affects subjective well-being by focusing on the psychological adjustment of middle-aged and older workers. Two web-based surveys were conducted at 1-year and 3-month intervals with 3540 workers aged 40 to 64 years, including those eligible for both position-retirement and reemployment. Factor analysis of CA in the first wave extracted two factors “control and confidence” and “concern and curiosity”. Multiple regression analysis, adjusted for important covariates, was conducted with the overall CA and the two factors of CA as the independent variables, and scores of the Satisfaction with Life Scale (SWLS) as the dependent variable. For satisfaction with life, only concern and curiosity had a significant positive association, while control and confidence had no significant association. Analysis by employment stage indicated that only concern and curiosity had a significant positive association with satisfaction with life, while control and confidence had no significant association with any employment stage. The results suggest that the effect of CA on satisfaction with life remains the same, even among those who are position-retired or reemployed at the end of their vocational lives, which is a transition period in their lives.