PURPOSE: To manufacture the alloy thin wire in which TixNiy precipitated products are suppressed and to obtain the Ti-Ni-Cu alloy thin wire of a circular section having ≥10at% Cu content at a low cost by substituting specified ratio or above of Ni in a Ti alloy contg. specified ratio of Ni by Cu.

CONSTITUTION: The Ti-Ni series shape memory alloy thin wire including Cu has the compsn. in which ≥10at% of Ni in an alloy constituted of 49 to 51at% Ni and the balance Ti is substituted by Cu. For manufacturing the thin wire, a coolant layer 9 is formed in a cylindrical drum 1 which is rotating by a centrifugal force, and the molten metal of the Ti-Ni-Cu alloy having the above compsn. is injected from an injection device 14 as a jet to solidity the above molten metal.