Abstract: According to the phase transition theory of titanium alloy, a new test method for phase transformation temperature of β-titanium alloy material was established. Samples were preheated and kept 30-50℃ above the theoretical phase transformation temperature for 40 minutes, cooled in the furnace to 650℃, and cooled in air. Phase transformation temperature was tested according to GB/T 23605-2009, the temperature range of plate-like α volume fraction less than 1% and equal to 0% was phase transformation temperature range of β-titanium alloy. The test results of phase transformation temperature of TC18, TB6, TB3, TB8 titanium alloy showed that the new method was feasible and made up for the deficiency of standard test method.