Dynamic infrared target simulator is one of the crucial equipments for infrared guidance weapon′s hardware-in-the-loop simulation platform.With the Digital Micro-mirror Device (DMD) as the key component,a dynamic infrared target simulation system was developed which will be used as the hardware-in-loop simulation platform for a certain type of air-to-ground missile seeker.DMD fundamental operating principle and gray imaging theory are explained thoroughly.Various key DMD subsystems such as DMD operating core,synchronization driving,data loading and PWM are designed elaborately and a dynamic infrared target simulator based on DMD has been developed.The practical experiment results prove that the above simulation system can satisfy all the design specification requirements and ideal simulation effects were obtained.