PURPOSE: To obtain a high joint strength by the simple method of joining Ni-Ti based alloy members to be used as a shape memory alloy and superelastic alloy.

CONSTITUTION: This method for joining the Ni-Ti based shape memory alloy members comprises arranging a multicore composite material 1 of a small wire consisting of ≥2 kinds of metals mainly composed of Ni and Ti or an alloy mainly consisting of the Ni and the Ti, respectively, between the plural Ni-Ti based shape memory alloy members 2 to be joined and alloying and joining these members by a combustion synthesis method.