Abstract: A down-load control strategy for supercharged boiler installation is put forward, which can increase the boiler's down-load speed and improve maneuverability of power system. By the simulation platform named SimuWorks, the down-load characteristic is analyzed based on the mechanistic models of marine supercharged boiler installation. The simulation result shows that the model has a high credibility, the error between simulation model and actual equipment is under 0.3%. The max valve-closed speed is 1.85 (°)/s, and it takes boiler 172 s to return stable. Down-load by steps will shorten elapsed time at least 43.78% to return stable, and the more steps, the less time spends.