The study investigated the relationships between job satisfaction and career transition competency among middle-aged and older employees. The study adopted a survey method and used purposive sampling to recruit middle-aged and older employees in Taiwan as study participants. A total of 512 questionnaires were distributed, with a response rate of 96.68%. Two survey instruments were used in the questionnaire, namely a job satisfaction scale and a career conversion ability Scale. The results of the study were that: 1. Subjects held a relatively positive and active attitude towards their career transition competency. Among the facets of career transition competency, career networks had the highest mean score, whereas individual career management had the lowest mean score. 2. Significant positive correlation was found between job satisfaction and career transition competency. 3. Significant explanatory power (R[superscript 2] = 0.45) was found in the factors of age, educational level, work place, reason for job change, and job satisfaction. The principal conclusion was that the government should collaborate with social education institutions to facilitate the education of middle-aged and older workers to help them better adapt to the changing employment environment, thereby improving their employment stability.