Abstract: By adjusting the current and voltage of three different primary smelting and tertiary smelting, TC6 titanium alloy ingots with a diameter of φ640 mm were prepared, and the uniformity of chemical composition and low-magnification structure were compared.Effect of different melting process parameters on soft segregation defects in TC6 titanium alloy was studied.The results show that the three methods can produce TC6 titanium alloy ingots with uniform chemical composition of φ640mm. Continuously reducing the smelting current in the middle of a smelting and using a shallow molten pool smelting method for finished smelting can effectively reduce the probability of soft segregation defects in TC6 titanium alloys. The smelting input power can be reduced by adjusting the smelting parameters, so as to reduce the macrosegregation of large-sized ingots.