The mold filling and solidification simulation for the high pressure die casting (HPDC) and Iow pressure die casting(LPDC) processes were studied. A mathematical model considering the turbulent flow and heat transfer phenomenonduring the HPDC process has been established and parallel computation technique was used for the mold fillingsimulation of the process. The laminar flow characteristics of the LPDC process were studied and a simplified modelfor the mold filling process of wheel castings has been developed. For the solidification simulation under pressureconditions, the cyclic characteristics and the complicated boundary conditions were considered and techniques toimprove the computational efficiency are discussed. A new criterion for predicting shrinkage porosity of Al alloy underIow pressure condition has been developed in the solidification simulation process.