The effect of mechanical alloying conditions on the characteristics of mechanically alloyed powder (MA powder) and its sintered alloys were investigated. The difference in sintering behavior between the MA powder and the elementally mixed powders by a V-blender (V-blended powder) and the microstructure and shape memory characteristics of the sintered alloys were also examined. The MA powder was fabricated by using a planetary ball mill and was sintered by a pulse-current pressure sintering equipment at various temperatures. The powder agglomerated and cold-welded and its particle size became larger with an increase in milling time. The mixture of Ti and Ni powders changed into an amorphous state by processing for 3.6 ks more than 500 rpm. The assintered alloy of the MA powder showed more homegeneous phase of TiNi than that of the V-blended powder produced in a same manner, however the former showed a lower density than the latter due to a larger particle size of its MA powder of before-sintering. The solution-treated alloy of MA powder showed more uniform microstructure of TiNi than that of the V-blended powder, and the relative density of the shape memory treated alloy was 100%. The shape memory treated alloy of MA powder showed good shape memory characteristics and 750 MPa in tensile strength.