Meta-stable β Ti alloys are very promising as biocompatible implant materials, because the low elastic modulus is expected. This work investigates the mechanical properties of Ti-3. 5mass%Cr-Sn-Zr alloys. We focus on the effect of the varying alloy composition on the microstructure, the Young's modulus, the deformation mechanism and the deformation behavior. Ti-3. 5mass%Cr based alloys with low Young's modulus are obtained in several suitable compositional combinations of Sn and Zr. The alloys with low Young's modulus consist in meta-stable β phase. The composition of the meta-stable β phase is close to the transition where the quenched microstructure transits from martensite to meta-stable β phase.