The dynamic infrared scene simulation system based on digital micro-mirror device (DMD) has been the hotspots and used widely. The operational principle of DMD and its gray modulation technology are introduced. The effect of matching of the detector integration time of and the DMD display time on system imaging is analyzed. The results show that the imaging aliasing can be eliminated when the above time satisfies a certain relation under static scene simulation,but under the dynamic scene simulation,the clear and complete image can be obtained when the external signal is only synchronous.