Based on theories on channel governance and management control, and from the perspective of the whole process of the development of trading relationship, this study used management control as a channel governance process mechanism, focused on the mediating effect of management control to safeguard the effective implementation of contractual mechanism, as well as the moderating role of farmers’ net specialized investment between contract completeness and management control. By investigating 217 survey data from the farmers in farmer/buyer relationships, this study found the three kinds of management control (outcome control, process control and capability control) play a mediating role in the process of improving the farmers’ performance by contract completeness, and process control also plays a mediating function in the process of restraining the farmers’ opportunistic behaviors by contract completeness. Meanwhile, high farmers’ net specialized investment weakened the positive influence of contract completeness on the three kinds of management control.