The work aims to improve the prediction reliability of elbow erosion during industrial production. In the Lagrangian coordinate system, the CFD-DPM model was used to solve the erosion problem of solid particles on the elbow under the action of fluid. The erosion velocity equation was used to study the relationship among fluid velocity, solid particle diameter and solid particle mass flow. The relationship between the erosion of the elbow and the maximum erosion position, simulation value and erosion of the elbow was studied to predict the maximum erosion position of the elbow erosion by simulation. The maximum erosion position of the elbow erosion by simulation was mainly concentrated on the horizontal sides of the elbow outlet and the vertical sides of the elbow inlet. As the solid fluid velocity u increased from 8 m/s to 18 m/s, the maximum erosion rate of solid particles to the elbow increased by 9.912 times, and the mass flow rate f of the eroded solid particles increased from 0.2 kg/s to 0.8 kg. The maximum erosion rate of the elbow increased by 4.527 times. When the diameter of the solid particles increased from 200 μm to 900 μm during the simulation, the maximum erosion rate of the elbow increased by 3.94 times. When the solid particle diameter, solid particle velocity and solid particle mass flow rate are constant, the elbow erosion increases with the increase of fluid velocity, and the elbow erosion region gradually increases at the horizontal position of the elbow outlet; when the diameter is increased and the fluid velocity is constant, the erosion at the bending position of the elbow is gradually increased under the action of inertial force, and the erosion on both sides of the elbow outlet is gradually reduced; the elbow erosion increased when the solid particle mass flow rate increases.