Abstract:The effect of Gamma ray radiation on the kinematic viscosity, pour point, acid value and other physical and chemical indicators of hydraulic oil were researched under the dose rate of 2 kGy/h and different radiation doses. The results show that the impact of the radiation dose on the kinematic viscosity of the hydraulic oil is relatively small and the kinematic viscosity is increased slightly with the increasing of radiation dose. The pour point is reduced with the increasing of radiation dose, which makes the low temperature fluidity of hydraulic oil better. The acid value of the hydraulic oil is greatly affected by the radiation does, and the acid value is increased significantly with the increasing of radiation dose. With the increasing of radiation, the chromaticity is increased, the color is deepened, and the light transmittance is deteriorated.