Transformation behavior and superelastic behavior of Ti-Ni-Cu alloys with various Cu content has been investigated by means of electrical resistivity measurement, X-ray diffraction, tensile test and transmission electron microscopy. Two types of heat treatment are given to the specimens: i) Solutions treatment. ii) thermo-mechanical treatment. The transformation sequence in solution treated Ti-Ni-Cu Alloys substituted by Cu for Ni up to 5at.% occurs to $B2{ ightleftarrows}B19^{prime}$ and it proceeds in two stages by addition of 10at.%Cu, i. e, $B2{ ightleftarrows}B19{ ightleftarrows}B19^{prime}$. Also, it has been found that Ti-30Ni-20Cu alloy transformed in one stage : $B2{ ightleftarrows}B19$. The thermo-mechanically treated Ti-47Ni-3Cu alloy transformed in two stages: B2${ ightleftarrows}$rhomboheral phase${ ightleftarrows}B19^{prime}$, while transformation sequence in Ti-45Ni-5Cu and Ti-40Ni-10Cu alloy transformed as same as solution treated specimens. The critical stress for inducing slip deformation in solution treated and thermo-mechanically treated Ti-40Ni-10Cu alloy is about 90MPa and 320Mpa respectively.