Abstract: For multivariable controller, we always face some troubles, such as that the design is complex, and the adjustment of the controller parameter is inconvenient, and the implementation is difficult and the engineering practicability is poor, and so on.In order to solve the problems, a multivariable decoupling internal model controller is proposed. As for the controller, the pre-feedback compensation is used to decouple, and two step design method is utilized to implement the controller, and the internal model controller and the decoupled control object are equivalently transformed into a PID controller with only one adjustable parameter. Experimental results show that the system decoupling effect is good, and the system exhibits good dynamic response characteristics by adjusting the unique parameter. In the case of model mismatch and interference, the robustness and anti-interference ability of the system is still good, and it has higher engineering application value.