Abstract: The flash method was used to measure the thermal diffusion coefficient, specific heat capacity, thermal conductivity and other thermophysical parameters of powder metallurgy beryllium materials. The sources of uncertainty in the measurement of thermophysical parameters were analyzed, and the uncertainty in the measurement of thermophysical parameters of powder metallurgy beryllium materials was evaluated. The results show that at a confidence level of 95%, the expanded uncertainty of the thermal diffusion coefficient of powder metallurgy beryllium material was 1.48 mm²/s, the expanded uncertainty of the specific heat capacity was 0.07 J/(kg ·K), and the expanded uncertainty of the thermal conductivity coefficient was 5.80 W/(m ·K).