Abstract: A DPF catalyst regeneration simulation model is established and simulated by GT-Power software package. The regeneration process has been optimized in view of the strategies of injection rate and auxiliary air. After the optimization, DPF heating time has been shorten by 37.9%,and the maximum outlet temperature has been increased by 3.4%. The PM combustion model of DPF is set up to analyze the temperature of filter and thickness of PM layer during regeneration process. The calculation results indicate that the temperature is gradually increasing from the front end to the back end of the filter and the maximum temperature appears at the center of back end. The PM is gradually burning from the front end to the back end of filter,and PM at the back end burns faster than that at the front end.