As the core component of a gas turbine, the turbine blade works at a high temperature of thousands of degrees for a long time. In order to ensure the safe and reliable bladeoperation, its temperature needs to be monitored in real-time. Radiation temperature measurement is currently the mainstream method of non-contact temperature measurement of gas turbine blades. Its temperature measurement accuracy is closely related to the reflection characteristics of blade materials. The difficulty of current research isto predict the reflected energy in different directions and reduce the impact of reflected radiation on temperature measurement. In order to predict the reflected energy of the turbine blade and improve the accuracy of radiation temperature measurement, the bidirectional reflection distribution function (BRDF) of completely oxidized DZ125, a common material of turbine blade, is studied in this paper.The reference method is used as the experimental measurement method. Firstly, the measurement principle and data processing method of the BRDF comparison method is analyzed. After that, the experiment platform was built independently. Under the conditions of 25, 900 and 1 100 ℃ and wavelength of 1 060, 1 550 and 1 908 nm, the incident zenith angle and reflection zenith angle were controlled to change in the range of 0° to 60°, and the azimuth angle changed in the range of 0° to 180°. Several groups of the BRDF values were measured and calculated, and the effects of various factors on BRDF of completely oxidized DZ125 were analyzed. Finally, the modified Phong model is used to fit the measured values of BRDF. The fitting results can be accepted accordingto the comparison with the experimental results. The results show that temperature and wavelength have little effect on BRDF of fully oxidized DZ125. As long as the temperature range of the turbine blade and the radiation wavelength does not change strongly, the effect of both on BRDF can be ignored.The incident zenith angle, reflection zenith angle and azimuth angle greatly affect BRDF. The closer the incident zenith angle and reflection zenith angle are,and the closer the azimuth angle is 180°, the closer the position of the measuring probe is to the specular reflection direction. Then the specular reflection characteristics of the sample are more significant, and the BRDF is large. On the contrary, diffuse reflection dominates when the probe is far away from the specular reflection direction, and BRDF decays rapidly. The experimental results show that completely oxidized DZ125 has strong specular reflection characteristics. The modified Phong model fitting results show the bidirectional reflection characteristics of fully oxidized DZ125. This model is simple and suitable for using Monte Carlo simulation to predict the distribution of the total energy of DZ125 oxidation.It provides a theoretical basis for the subsequent study of the radiation temperature measurement of turbine blades.