The WC-12wt%Co plate-like grain cemented carbides were prepared from plate-like W Co C (carbon black) base mixed powders. Effects of addition of nanometer tungsten powders and sintering processes on the microstructures and properties of plate-like grain cemented carbides were researched. It showed that the relative density of the WC-12wt%Co plate-like WC grain cemented carbides were near complete densification reached to 97%, the hardness of the alloys were exhibited obvious anisotropy, increasing the sintering temperature and prolonging sintering time or addition of nanometer tungsten powders were favor to sintering densification and the formation of more plate-like WC grains.