Aiming at the problem of solid particle erosion of titanium alloy materials, the nonlinear dynamic numerical simulation based on the finite element method is an important tool to study the high temperature erosion and failure mechanism of materials, which can effectively make up for the lack of detailed description in erosion experiments. In this paper, a systematical numerical simulation study on the erosion characteristics and energy conversion characteristics of multi-particle impact on Ti-6Al-4V titanium alloy target material was performed with the help of explicit dynamic finite element analysis, the Johnson-cook material model and the strain accumulation failure criterion model. Before calculation, the maximum Mises stress and the maximum indentation depth were used as the evaluation indicators, and a grid independence verification of the calculation model was carried out to determine the number of grids and the minimum grid size of the calculation model. After that, the effectiveness of the numerical method adopted in this paper was verified by comparing with the calculation results of the Hertzian elasticity theory, and the error between theoretical calculation and numerical simulation under different working conditions was less than 8.4%.