To calculate soot for a high-pressure common rail diesel engine a new soot model (TP model) is presented.. In soot source term phase, when zone temperature T<1500K, gas-phase kinetics is considered and the soot precursors –PAHs (Polycyclic aromatic hydrocarbons) is calculated. When zone temperature T ≥ 1500K, the gas-phase chemistry and soot source terms are calculated. The soot model integrated with the new auto-ignition models is then applied in multidimensional simulations. The TP model is then implemented in KIVA code instead of original model to carry out optimizing. The results of soot with variation of injection time, variation of rail pressure and variation of speed among TP model, KIVA standard model and experimental data are analyzed. The results indicate that the TP model can carry out optimization and CFD (computational fluid dynamics) and can be a tool to calculate for a high-pressure common rail directed injection diesel engine.