Subordinate trust as an important dependent variable of leadership behavior and the key independent variable of organization performance, its medium function between county magistrate leadership behaviors and government performance cannot be ignored. This paper regards social exchange theory and transformational leadership theory as a foundation, through an empirical research approach to analyze the mediating role of subordinate trust. Research results show that the mediating effect of subordinate trust exists between county magistrate leadership behaviors and county government performance. Among that, the impact of transformational leadership behavior to the government performance through subordinates trust is stronger than transactional leadership behavior's. The indirect effect from county magistrate leadership behavior to government performance has the same direction as the direct effect between these two. Furthermore, population control variables such as gender, age, length of work have no significant influence.