Background: Job satisfaction and quality of life among home care workers who serve simultaneously as informal carers for their own family members have seldom been explored. This study examined how this dual role influences job satisfaction and quality of life by comparing these dual carers with home care workers who do not provide informal care. The study also explored whether the factors related to job satisfaction and quality of life between these two groups were different. Method: Standardized self-administered questionnaires (Job Satisfaction Survey, the World Health Organization Quality of Life (WHOQOL) scales and various social demographic questions) were administered to the two groups of home care workers in Taiwan from March to April 2009. A total of 1,641 home care workers working in 119 non-government organizations sponsored by 23 local authorities completed and returned the questionnaires. Results: The two groups did not differ in individual characteristics, work characteristics or job satisfaction. Analysis results indicate that the lowest mean scores for all home care workers were the domains of promotion and pay within their job satisfaction and the domain of environment within their quality of life. Conclusions: Multiple regression analysis revealed a significant effect of unpaid caregiving in terms of quality of life but not in terms of job satisfaction. Moreover, job satisfaction and quality of life among home care workers were significantly determined by both their work conditions (e.g. travelling time, salary and length of work experience) and personal variables (e.g. age, family income and family support).