The erosion behavior of Ti-6A1-4V alloy was studied under ambient conditions using a sand-blast type test rig and silicon carbide particles. The effect of microstructure and mechanical properties on erosion was evaluated by heat treating the alloy at different solution treatment and aging temperatures for different lengths of time. It is found that erosion rate increases with the precipitation on aging, but decreases with overaging due to the agglomeration of precipitates. Erosion rate decreases with the increase in ductility occurring as a result of the changes in heat treatment. The effect of impingement angle, impact velocity and erodent particle size on erosion rate was investigated. The erosion mechanisms were studied by scanning electron microscopy. The material removal in erosion is attributed to cutting, ploughing or pile-up leading to flake formation and separation, and lip fragmentation.