The effect of heat treatment on torsion characteristics of high nitrogen steel wire has been studied by torsion test, tensile test, specific resistivity, X-ray diffraction and scanning electron microscopy. After heat treatment at 600∼$700^{circ}C$, torsion cycle was increased with increasing temperature. Especially, in case of high nitrogen steel wire heat teated at $650^{circ}C$, torsion cycle was sharply increased. It is estimated that cold worked high nitrogen steel wire started to recrystallize and phase transform at 64$0^{circ}C$ in air atmosphere.