Abstract: To meet the sealing performance requirements, the sealing cone surface of the valve core-valve body coupling is often processed through matching technology. However, there is no clear understanding of the impact of matching process parameters on surface quality at present and the selection of matching process parameters is more dependent on the experience and subjective feel of the workers. The matching process of the sealing cone surface of the 38CrSi high-strength steel valve core-valve body coupling is studied and the influence of three important factors, namely particle size of grinding paste, grinding speed,and grinding time,on the surface quality of matching process are clarified,which provided a reference for the optimization of the matching process and the realization of automatic matching process