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For nuclear radiation n-γ mixed field, a kind of environment-friendly ray flexible synthetic shielding material is developed. The material uses Gd as the core shielding particle and SEBS as the matrix. It has the characteristics of environmental protection, production energy saving, comprehensive protection, flexible plastic, recyclable and so on. Scanning electron microscopy (SEM) shows Gd2O3 powder distributes uniformly in granular form and has excellent dispersion in the matrix. X ray diffraction spectroscopy (XRD) and fourier-transformed infrared spectroscopy (FT-IR) show that Gd2O3 and SEBS are essentially physico-mechanical mixtures, and do not involve changes of chemical bond. The shielding results of γ ray and thermal neutrons show that with the increase of Gd areal density, the transmittances of γ ray and thermal neutrons follow the exponential attenuation law. When the Gd areal density is 0.018 4 ~ 0.291 3 g/cm2, the γ ray transmittances of material at 39 keV, 59 keV and 122 keV are 11.48%~83.73%, 2.73%~75.43% and 51.64%~93.03%, respectively. When Gd areal density is 0.018 9 ~ 0.070 9 g/cm2, the neutron transmittance of material is 35.78%~45.74%. This flexible ray shielding material effectively makes up the disadvantages of traditional shielding materials. It has potential application values in the biological shielding in ships, nuclear medical diagnosis and treatment, radiographic testing and other fields.