In the present study, solid particle erosion of Ti-6Al-4V alloy under multiple particles impact was investigated using finite element modeling. The erosive behavior of this ductile alloy has been simulated as a micro-scale impact model based on Johnson-Cook plasticity and failure equations. Erosive behavior is usually described by the volumetric erosion rate, which is introduced as the eroded volume ratio of alloy surfaces to the mass of the eroding particles. In this paper, the results of the finite element model were validated by comparing with results of typical erosion models. Then, effective factors on erosive behavior of alloy, such as impacting particles velocity, particles size, particles impact angle, temperature effects, and particles shape will be investigated. Results show that there is an exponential relation between particle velocity and erosion rate. Also, as particle size increases, the erosion rate increases at first and after a specific particle size, erosion rate presents a constant trend. The maximum erosion rate has been recorded at an impact angle of 40 degrees and a temperature of 473 Kelvin (average temperature of the middle stages of the compressor). It is shown that when spherical particles shape changes to the angular shape, the erosion rate increases more than four times.