The aim of this study is to explore the effects of employment status change on perceived organizational support and organizational commitment, as well as the moderating effect of locus of control. The research data was collected by questionnaires from 330 workers employed in 26 government agencies in Taiwan, whose working status were changed from contingent to permanent. By using t-test and hierarchical regression analysis, the result from the empirical study show: (1) The change of employment status will increase the employees’ perceived organizational support and organizational commitment. (2) The change of employment status will increase organizational commitment through the influence of perceived organizational support. (3) There’s no moderating effect of locus of control between perceived organizational support and organizational commitment. (4) Workers with higher education level show lower perceived organizational support, and some employees still disagree that the change of employment status increases their perceived organizational support.