Objective To analyze the effects of fluid parameters, sand parameters and environment parameters on erosion failure in elbow for liquid-solid two-phase flow. Methods Software FLUENT was used to simulate the elbow erosion-corrosion and analyze the influence of flow velocity, particle diameter, sand mass flow, operating pressure and gravity direction on elbow erosion. Results As the flow velocity increased from 2 m/s to 10 m/s, the maximum erosion rate increased from 8.86×10-8 kg/(m2?s) to 2.45×10-7 kg/(m2?s). As the particle diameter changed from 75 μm to 200 μm and then grew up to 550 μm, the maximum erosion rate first decreased from 2.04×10-7 kg/(m2?s) to 1.5×10-7 kg/(m2?s) and then increased up to 2.66×10-7 kg/(m2?s). As the sand mass flow increased from 0.05 kg/s to 0.25 kg/s, the maximum erosion increased from 8.56×10-8 kg/(m2?s) to 3.20×10-7 kg/(m2?s). As the operation pressure of tube increased from 0.1 MPa to 0.9 MPa, the maximum erosion rate decreased from 1.50×10-7 kg/(m2?s) to 1.25×10-7 kg/(m2?s). As the direction of elbow outlet turned from vertical downward to upward, the erosion rate gradually increased from 1.50×10-7 kg/(m2?s) to 1.86×10-7 kg/(m2?s). Conclusion Velocity and erosion have a positive correlation. As the particle diameter increases, the maximum erosion rate first decreases and then increases. In a certain range, maximum erosion corrosion rate increases as mass flow rises. The change of pressure in the tube is not obviously influential to the erosion weakening. Erosion damage is the most serious when the elbow outlet faces vertical upward.