In the actual operation of butterfly valve, the butterfly valve is found severe erosion wear. A solid particle erosion analysis of butterfly valve based on the erosion theory is researched in this study. A CFD model has been built to simulate the flow erosion. Different parameters of butterfly valve including inlet velocity, particle mass fraction and solid particle diameter are separately analysed. The results show that erosion rate increase with the increase of inlet velocity, particle mass fraction and solid particle diameter. The peak erosion rate is up to 4.63E-5 (kg/m 2 /s) and erosion of valve disc mainly occurs around the upstream edge and the cylinder face.