Titanium and its alloys are widely used as biomaterials. This study provides a detailed study of the effect of the chemical composition and heat treatment conditions in alloys belonging to the Ti15ZrxMo system. The aim is to optimize the mechanical properties of the alloys for use in orthopedic implants systems. The alloys were melted in an arc voltaic furnace, with four different alloys compositions: Ti-15Zr, Ti-15Zr-5Mo, Ti-15Zr-10Mo and Ti-15Zr-15Mo, allowing samples to be obtained with α, α+β and β phase microstructures. The heat treatments conditions were 600ºC/6h, 12h and 24h, 900ºC/8h and 1000ºC/8h. For the as cast alloys, in the Ti-15Zr it was only possible to observe the presence of a lamellar structure composed of α phase, the Ti-15Zr-5Mo shown a microstructure of β phase matrix with fine needle of α phases at the grain boundaries. The Ti-15Zr-10Mo and Ti-15Zr-15Mo alloys showed only beta type grain boundary. Consequently, the hardness of the materials increased with the raise of the amount of Mo in the alloys, while the elastic modulus decreases. Also, it was observed that the mechanical properties of the β alloys can be tailored by heat treatment, essentially when it is carried out at 600°C (Financial support: CAPES, CNPQ FAPESP).