In order to deeply study the grinding temperature and heat distribution ratio of nano cemented carbide,and explore the differences between cemented carbide with different particle sizes,so as to provide reference for grinding and quality control of cemented carbide with various particle sizes,three kinds of cemented carbide which main component was nano cemented carbide GU092 were selected for grinding test.The results show that compared with ordinary cemented carbide,nano cemented carbide has lower grinding temperature and higher heat distribution ratio,about 2.5%~11.8%; the grinding temperature decreases with the grain size,the plastic deformation of the surface of fine-grained materials is small,and the energy consumed in grinding is less; the heat distribution ratio increases with the grain size,and the fine-grained cemented carbide has stronger physical and mechanical properties and better thermal conductivity.On the premise of considering the machining efficiency,appropriately reducing grinding depth and increasing feed speed will help to reduce the temperature and improve the quality.