Abstract: The PP-foamed injection-molded products were processed by a microcellular foaming injection-molding method, and the effect of mold temperature on the mechanical properties and cell structure of the products were investigated by scanning electron microscopy, bending strength, impact strength and surface roughness. The results indicated that the cells of the products became denser with an increase of mold temperature, which led to an improvement in bending and impact performance but a decrease in surface roughness. The average diameter, density and dimensional standard deviation of the cells were simulated by a Moldex3D software, and the simulation results indicated that the standard deviation of cell size decreased with an increase of mold temperature, and the cell distribution also became more uniform. Moreover, the simulation also confirmed that that the trend in variation of mold temperature and weight loss ratio of cell was in a good agreement with the experimental results.