Ti-6Al-4V (Ti64) is the most popular alpha-beta titanium alloy employed in the aerospace industry. Ti64 is developed in many modifications of the basic formulation to gain favorable properties according to different applications. The heating temperature and cooling conditions are the basis of the titanium alloy’s heat treatment resulting in various microstructures which influences the machinability of the Ti alloys and other alloys. This research investigates the effect of Ti64 microstructure on the grinding forces and surface roughness in the surface grinding process using a resin-bonded cBN wheel. The grinding process of Ti64 with a fully elongated alpha microstructure (Ti64-Elo) produces smaller grinding forces than those with Ti64 samples with a fully lamellar microstructure (Ti64-La). For the same cutting conditions, the Ti64-La surface shows a gain in hardness compared to the Ti64-Elo one.