In this study, we quantitatively investigated the influence of the bottom shape of an agitated vessel stirred by dual impellers on the distribution of solid concentration and the optimal bottom shape of the vessel for the dispersion of solid particles was evaluated. Four types of bottom shapes were adopted, including a flat bottom tank (FBT), a profiled bottom tank (PBT), a semi-elliptical bottom tank (EBT) and a cone and fillet tank (CFT). It was found that a good dispersion of solid can be obtained in the order of EBT, PBT, FBT, and CFT at constant power consumption. The CFD simulation conducted in this work also showed that the area of lower velocity zone was small in the same order of EBT, PBT, FBT, and CFT. From the result obtained in this study, it is clarified that the distribution of solid concentration in the vessel is considerably influenced by the local flow formed at the bottom region of the vessel.