Abstract: The elastic modulus E of GH5188 alloy during heating up was measured by dynamic method. Based on the empirical formula E=E₀（1-ηT）, a two-stage linear fitting method was proposed to solve the threshold temperature T₀, which can quickly determine the applicable temperature range in which the elastic modulus of GH5188 alloy linearly decreases with the increase of temperature. The accuracy of the symmetrical beveled heat-resistant brick supplemented by heat-resistant cotton support method instead of the suspension wire method was verified for elastic modulus measurement through comparative experiments at room temperature. Moreover, the feasibility of this method under high temperature was discussed.An experimental method that was proposed by combining temperature raising and lowering can reduce the experimental time by nearly 40% while satisfying the measurement accuracy of threshold temperature.