The specimens manufactured using principle LS (Laser sintering) by the additive manufacturing technologies from the Ti-6Al-4V (Grade 5) titanium alloy are investigated. The powder Ti-6Al-4V is well-known for its slightness and high strength. Metal additive manufacturing processes produce parts with porosity. The possibility of changes in a porosity during an additive manufacturing build may also be an indication of problematic points during the process. This paper is investigated our work to monitoring of part porosity during an additive build, including characterization of mechanical properties such as the average yield strength (YS) and ultimate tensile strength (UTS) , and elongation. Also, the development and detailed characterization of microstructures were carried out.