Cemented carbide is a kind of multicomponent polyphase material, and its manufacturing process involves complex thermodynamic and kinetic processes. In order to provide a theoretical basis for the development of cemented carbide, based on the established thermodynamic database CSUTDCC1, the CALPHAD simulation results were compared with the experimental results in other literatures to verify the accuracy and efficiency of the thermodynamic calculation method. To demonstrate the application of thermodynamic calculation in the design of cemented carbide, including the control of alloy composition, the confirmation of sintering temperature and N2 atmosphere, the saturated solubility of Cr, V, Ta, Nb and Zr in cobalt bonding phase and M6C carbide was studied by thermodynamic calculation and experimental verification. The specific role of thermodynamic calculation in the development of cemented carbide was discussed.