Abstract: 　　The effect of Fe content on melting temperature of TC4 titanium alloy was studied. Three groups of titanium alloy-high temperature alloy, titanium alloy-stainless steel, and titanium alloy-stainless steel were annealed at 1170°C for 40 min in a gas quenching furnace. The composition of the melt was analyzed by Brooksititan 300 spectrometer and Axio Observer.The results show that when the temperature rises to the Fe-Ti eutectic temperature (lowest eutectic temperature of 1085C), The eutectic compound(FeTi) is formed by eutectic reaction in the low melting point eutectic region, and the eutectic structure of β-Ti and FeTi melts to form multiphase liquid phase with the increase of temperature, which reduces the melting
　　temperature of titanium alloy. This study can provide theoretical guidance for vacuum heat treatment of TC4 titanium alloy components used in aviation.