In this study, it is aimed to investigate the effects of particle impingement angle and velocity on the surface roughness, erosion rate, and surface morphology of solid particle eroded Ti6Al4V alloy. Ti6Al4V samples were eroded in erosion test rig under various particle impingement angles (15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees and 90 degrees) and impingement velocities (33 m/s, 50 m/s, and 75 m/s) by using 120 mesh garnet erodent particles. Subsequently, erosion rates and surface roughness values of samples were analyzed and calculated as a function of particle impingement angle and velocity. Moreover, 3D surface morphologies of the eroded samples were prepared by using high definition scanner and image processing programs. Results show that erosion rates, surface roughness values and surface morphologies of Ti6Al4V alloy have been varied significantly depending on the both particle impingement angle and velocity. Erosion rates of Ti6Al4V alloy were decreased with increases in particle impingement angle; on the other hand, the surface roughness values were increased with increases in particle impingement angle. Both erosion rates and surface roughness values were increased with increases in particle impingement velocity. Finally, the surface morphologies of the eroded samples were evaluated deeply. It is concluded that the surface morphology variation of the Ti6Al4V alloy depending on the particle impingement angle and velocity were well correlated with the erosion rates and the surface roughness values.