Abstract: The melting peak temperature, crystallization peak temperature, glass transition temperature extrapolation starting temperature T_eig and midpoint temperature T_mg of polyetheretherketone materials for implanting medical devices were measured by differential scanning calorimetry. The effects of repeatability of test results, error of equipment indication and standard value of standard material on test results were analyzed, and the corresponding uncertainty was evaluated. The results show that increasing the number of experiments could effectively reduce the uncertainty of the measurement results of T_eig and T_mg.