Propulsion system is the power source of ship. In recent years, the shipbuilding industry of our country has developed rapidly, and the requirement of ship propulsion technology is higher and higher order to meet the propulsion requirements of modern large ships, controllable pitch propellers with high propulsion power and high control accuracy are widely used. Adjustable pitch propeller can according to the actual conditions of the ship (speed and load) adjust the pitch angle, so as to improve the propulsion efficiency of the propeller and ship maneuverability, improve shipping capacity, is a widely used propeller. Aiming at the problem of automatic control of ship controllable pitch propeller, introduces the system of nonlinear PID control technology, on the basis of the research on the marine controllable pitch propeller control system based on PID, and a controller based on nonlinear PID control technology is designed, which can make the response speed of ship pitch propeller faster and solve the problem of pitch Angle overadjustment of ship pitch propeller, and the system simulation.