Considering the features of the pressurizer pressure, such as large inertia, multiple disturbances, complex nonlinearity and difficulty in obtaining accurate mathematical models, and in view of the dynamic characteristics of unstable open loop of the pressurizer pressure, a predictive control system is devised in this paper. Firstly the dynamic matrix predictive controller is designed with the model self-stabilization of the non-stabilization system, and in order to solve the engineering implementation of this control method, the control signal output is obtained. Finally the control system simulation platform is built on MATLAB/Simulink. Simulation and disturbance test show a superior control performance and strong anti-disturbance ability. It provides a solution for the application of dynamic matrix control in the non-stabilization system.