Abstract: Dissolving behaviour of WC in WC/steel composite material has been investigated.Qualitative and quantitative analyses of the phase composition have been conducted with an electron probe and SEM. The phase structure analyses have been performed by using an X-ray diffractometer.The microstructure of the composite material has been examined by using optical microscope and TEM. Results are shown that dissolving and precipitation processes between WC and steel matrix of the WC/steel compolite material occur during sintering and heat treatment because of the interaction between WC and steel matrix,and the chemical composition of the matrix changed.This may affect the heat treatment process and the structure and properties of the composite material.