Surface-type infrared decoy has been an effective jamming method for defending infrared imaging guided anti-ship missile. This paper takes surface-type infrared decoy defending anti-ship missile using centroid jamming as examples,the simulation models including missile model,ship model,surface-type infrared decoy model,decoy launching model and evaluation model of launching and maneuver’s influence on jamming effectiveness,etc,are designed. Then according to computation flow of centroid jamming,the optimal scheme of decoy launching and ship maneuver is found. Finally,the rules and methods of decoy launching and ship maneuver are put forward when applying surface-type infrared decoy.