Airborne infrared countermeasures system is developing towards systematization and integration.As an important jamming means in infrared countermeasures, the cooperative usage of infrared jamming projectile and directional infrared countermeasure system is a key.By analyzing the interference mechanism of infrared jamming projectile and directional infrared countermeasure system, an integrated infrared countermeasure system model is established, and the procedure and rules of cooperative usage are studied.The effectiveness of the cooperative usage strategy for orthogonal quad-element infrared seeker is verified by simulation.