The undisputable advantages in terms of time and cost saving for soot emission study have made the computational analyses becomes more preferable. Current development of computer program with higher precision mathematical model making simulation works becomes closer to the real engine combustion environment. This investigation for in-cylinder soot concentration has been carried out using a commercial Computational Fluid Dynamic (CFD) software, CONVERGE CFD. In conjunction to explore its full capability, study on soot has been performed using different level of complexity soot model, from simple two-steps of Hiroyasu-NSC soot model to the detailed-kinetic soot model. Both detailed soot model which based on methods of moment and sectional method are applied in this study. The result show that simpler soot model will overestimated the soot mass value while detailed soot model will provide extra information of soot size, number density, volume fraction and soot mass for every related soot process. Results of emission species (CO, NOx, HC), formation species (A3R5-, C2H2), oxidation species (O2, OH) as well as fuel species (C7H16) also been reported in this study. In overall, detailed soot model which consider more factors in soot formation and oxidation process will provide lower soot mass concentration than simple soot model. In addition, CONVERGE-CFD software is an attractive option to study various soot parameters as it can analyze the soot concentration using detailed soot model, as a comparison to simpler soot model.