Spherulites in semicrystalline polymer grow dramatically during injection molding. This work has experimentally measured the spherulite size from actual molding process. The distribution of spherulite sizes are scrutinized over molded specimens. The thermal history of melt is dramatically different according to the location in the thickness direction. In the skin where the melt directly contacts the mold, solidification takes place quite rapidly. Thus, as is well-known, very small spherulites are observed near the skin layer. In the core layer far from the skin, quite large spherulites are formed, whose dimension can be over 0.1mm. In addition to this, this work has investigated spatial variation of the distribution. The specimen has been properly sliced and microtomed to very thin sections. From polarized optical microscopic images, spherulites are examined and their dimensions are measured. The distribution of spherulite dimension has been compared with simulated temperature and frozen layer thickness.