PURPOSE: To stably obtain a shape memory alloy reduced in hysteresis by heating and cooling an Ni-Ti alloy with a specific composition, cold-working the above at a temp. in a specific temp. region, and then applying aging treatment to the above.

CONSTITUTION: An alloy having a composition consisting of, by atom, 49.0-50.3% Ni and the balance Ti with inevitable impurities is subjected to solution heat treatment consisting of heating at 600-1,000°C and cooling. Subsequently, cold working of 5-60% draft is applied to the above while regulating the temp. to ≤60°C, followed by aging treatment at 300-550°C. Since effects sufficient for reducing hysteresis are produced by the above regulation of cold working temp., the Ti-Ni shape memory alloy reduced in hysteresis can be effectively manufactured.