New Public Management posed challenges to governments by emphasizing the flexibility of workforce, innovation, and the role of supervisors in running public sector organizations. However, there is debate over whether job insecurity and organizational innovativeness contribute to organizational performance in the public sector. Furthermore, despite the growing awareness of the importance of supervisors, the issue of public sector employees’ trust in their supervisors has received relatively little attention. The purpose of this article is to examine the impacts of job insecurity, innovation, and employees’ trust in supervisors on organizational performance in order to explain these inconsistencies and fill the void in past research. It develops a structural equation model, built on two sets of Korean public employee survey data, whose results show that job insecurity is negatively related to performance, while employees’ trust in supervisors and organizational innovativeness are positively associated with performance. In addition, employees’ trust in supervisor is positively related to innovativeness.