By utilizing the FLUENT software, finite element simulation analysis was performed on the two-phase separation of powder injection molding, and the simulation results were verified through experiment. As indicated in the simulation results, the optimal process parameters for the injection molding of 316L stainless steel sample were to inject at 70 MPa and 140 °C, at an injection speed of 3.49 cm3/s. Under these conditions, the maximum average solid volume fraction in observation area of the sample was 57.68 %. Additionally, it was discovered that while preparing 316L stainless steel was prepared by powder injection molding, the smaller the average porosity of the sample, the greater the Vickers hardness. And then the higher the average solid volume fraction simulated the slighter the two-phase separation between the powder and the binder. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.19137