The effect of cooling profiles on the average crystal size and aspect ratio was studied as an example of the application of two-dimensional population balance model. The nonseeded cooling type batch crystallization system was chosen for this study. The simulation successfully provided the information about the crystal size distribution and the average aspect ratio of each crystal product obtained through different cooling profiles. In addition, using the proposed model, it was expected that the modulate cooling in which undersaturation is introduced during the cooling operation, that has already been reported in previous research as an effective method to improve crystal size distribution, is also applicable for the improvement of aspect ratio. However, it was also implied that the results were influenced by various factors such as nucleation rates, growth rates, and dissolution rates of length and width.