Ti-6Al-4V titanium alloy due to strength to weight ratio and corrosion resistance has many applications in aerospace industries. However, this alloy shows poor wear resistance especially under high loads. In this article, with the aim of improvement hardness and wear resistance of Ti-6Al-4V titanium alloy, B4C hard particles has been added to the molten pool in TIG welding process. Microstructural investigations via XRD and SEM showed that B4C particles almost completely solved in titanium matrix and with the arrival of boron and carbon in molten titanium, phases based on TiB and TiC has been formed. Phase morphologies based on TiB was blade and eutectic shape and TiC phase was spherical like. The results showed that surface hardness is equal 1020 Vickers that is approximately 3 times more than the bare alloy.