In this study the numerical calculations of the spray characteristics in a quiescent environment and in a motoring condition of direct injection diesel engine were performed to study the effect of breakup regimes on the spray characteristics. The breakup models used were Reitz & Diwakar model and TAB model. In the quiescent condition, spray tip penetration and spray tip velocity were predicted and compared with the experimental results. The predicted results using the TAB model were in qualitatively better agreement with the experimental ones than those using the Reitz & Diwakar model. In the motoring condition, as the initial SMD increased, the evaporation rate was greatly changed with the breakup model.