Aiming at the huge amount of data and the need for high transmission bandwidth in infrared search and track system,the JPEG compression algorithm is introduced into the system.The JPEG algorithm and its various modules are discussed in detail.The approaches to realize the function of the modules are described.The test results are given out by programming and simulating with graphical language in System Generator software.Finally,the method is applied in the practical infrared search and track system developed recently.In the practical system,the infrared images collected by the front units can be transmitted to the command and control center smoothly with a limited bandwidth.