The simulation of squeeze casting process of a magnesium alloy wheel was practice. Using professional casting software, the temperature field during filling and solidification process, and then the potential defects were forecasted and previewed. It was found that there would be shrinkage defects at the center and the junctions between the rim and the spokes of the wheel. It is better to choose a mould temperature for a better cast property at meet of full-filling. Number of programs are analyzed and compared through orthogonal experiment. And the best parameter team is educed through analysis. It is confirmed that the potential micro-shrinkage is reduced by simulated again using the best parameter team. And the cast property is enhanced.