Foam contained plastic products have an advantage of light weight and lower grade of injection molding machine for fabrication. In this research cell formation characteristics have been discussed in chemical blowing agent contained PP for diverse injection molding conditions. Chemical blowing agents used in this study were inorganic based blowing agents. Injection molding conditions are divided into two parts, one is a molding condition and the other is a plasticizing condition. Molding conditions are injection temperature and injection speed. Plasticizing conditions are barrel temperature, screw rotation speed, and back pressure in the injection unit of injection molding machine. Injection pressures of injection molding machine and cavity pressures were measured according to the injection molding conditions. Cell formations on the cavity were observed by an optical microscope by cutting the specimens and discussed using an image processing software for injection molding conditions. Weights and dimensions of specimens were also measured and compared with specimen molded by general injection molding with PP that does not contained any blowing agent.