The flow behavior and wall wear of a ball seat in frac sleeve with cone shapes have been studied numerically.The gas flow fields were simulated by means of standard k-εmodel. The effect of instantaneous turbulence on particle tracking was taken into account with the stochastic tracking approach in discrete phase model（ DPM） using Lagrangian method. The flow behavior during the cone part in ball seat was presented,and the changes of flow field and wall wear in ball seat caused by different cone shapes also can be predicted by CFD simulation. The results indicate that The distribution of the flow field in the large column section and the small column section of the ball seat is relatively uniform. Due to the wall effect of the sand,the flow field in the near wall has certain fluctuation. Optimized double cone structure can control the mainstream velocity gradient and sand concentration,and based on that this new design can reduce ball seat wear. Results obtained from the computer modeling have demonstrated the CFD is suitable for modeling an effect of wearing in ball seat on its performance.