Among the engineering alloys, NiTi has a special position due to its properties such as strength, biocompatibility, shape memory and superelastic behaviors. The addition of alloying elements to the NiTi compound changes critical temperatures of phase transformation and thus shapes memory properties. The replacement of titanium with vanadium, chromium, manganese or aluminum, as well as the replacement of nickel with cobalt or iron, leads to a decrease in the temperatures of phase transformation and also to an increase the strength by solid solution mechanism. In order to improve the superelastic effect of NiTi alloys, various thermomechanical processes have also been used. In this study, the effect of vanadium addition and thermomechanical processing including severe cold rolling and subsequent annealing on structural changes and mechanical properties of NiTi alloy have been investigated. For this purpose, samples containing 0, 1, 3 and 5 atomic percentage vanadium were fabricated by a home-made copper boat vacuum induction melting system. After the homogenization treatment, cold rolling up to 40% reduction of thickness and subsequent annealing at 400 ° C for 1hr was carried out. The results showed that vanadium replaces titanium in the binary composition of NiTi. Generally, vanadium reduces the temperature of the phase transformation; however, in Ni-Ti-V alloys containing more than 3% vanadium, due to precipitate formation and nickel reduction in the matrix, the critical temperatures increased and the values As= 68°C and Ms=43°C were obtained. In the vanadium-free sample, thermomechanical processing reduced the critical stress of the phase transformation by 50 MPa and improved the residual strain by 20%. With the addition of 1% vanadium to the alloy, thermomechanical processing increased the critical stress to 330 MPa and strain recovery up to 80%. The initial temperature of the martensitic transformation was changed to -63°C and the austenite start temperature was 35°C. The specimen containing 3% atomic of vanadium, due to the formation of precipitates and to decrease critical temperatures, showed shape memory effect with plastic deformation at room temperature; however, cold rolling of the sample containing 5% atomic vanadium was not possible, due to the formation of brittle and fragile particles.