Abstract: An infrared-imaging model for a CFD turbulence flow field was established with light ray tracing. It uses a “digital picture” to simulate an “actual target” to carry out simulation and calculation. It is concluded that there are blur effects of the wall-attached layer on a hypersonic missile by comparing the original picture with the simulated picture. It provides the missile computer the theoretical support for recovering images. This paper categorized the models into three types, long-distance, critical-distance and short-distance, according to the operation concept of infrared seeker. All these models were discussed respectively. The relationship between the PSF and the blur board used in digital image processing was analyzed.