Background: The purpose of the study was to explore the job stress and job satisfaction of nursing assistants (NAs) in Taiwan. The research took place in a public hospital where NAs were supplied by a contracting agency that tendered every two years for the business of supplying personnel. The performance of the NAs was appraised every month, with the results being subsequently reported to the contractor and to hospital administrators. The NAs had to tackle a wide range of complex tasks, resulting in a heavy workload with high pressure. They were paid 30,000 Taiwanese Dollars per month (about 836 GBP). Lack of employment protection sometimes resulted in high turnover rates with concomitant difficulty in recruiting new workers. Methods: This study adopted a cross-sectional research design and used the Minnesota Satisfaction Questionnaire in conjunction with the Chinese variant of the Job Content Questionnaire to explore the relationship between job satisfaction and job stressors of NAs. A total of 172 valid questionnaires were received, with an effective response rate of 89%; 84% of the respondents were female, and 71% of the sample possessed more than 6 years of professional experience. The data were statistically analyzed including SPSS For Windows 20.0, independent sample t-tests, and regression analysis to calculate the correlation between job stressors and job satisfaction. Results: Respondents’ level of intrinsic, extrinsic and general satisfaction was enhanced by “skill discretion” (i.e., job creativity), work autonomy and social support from management and colleagues. The nursing assistants in this study had relatively low job stress and high job satisfaction. Conclusions: Despite some encouraging findings, the unstable working environment of NAs constitutes a hidden worry for the development of long-term care in Taiwan. Social support is crucial to satisfaction; on-the-job training, and work in interdisciplinary teams, would help establish sustainable professional development; and a career path with promotion opportunities would further increase job satisfaction. Trial Registration: not applicable though ethical approval was granted for implementation of the study.