To improve the safety performance of hexanitrohexaazaisowurtzitane (CL-20) and maintain its higher energy, three kinds of CL-20/FOX-7 polymer bonded explosives(PBXs) with different formulation proportions were prepared by water suspension coating method using polyurethane polymer Estane as coating agent and 1,1-diamino-2,2-dinitroethene(FOX-7) as energetic sensitivity-reducing component. The morphology structure, crystal form, thermal decomposition characteristic and impact and friction sensitivity of samples were tested and analyzed by scanning electron microscopy (SEM), X-ray diffractometer (XRD), differential scanning calorimeter (DSC), impact sensitivity tester and friction sensitivity tester. The detonation velocity of three kinds of PBXs was tested by an electrical measurement method. The results show that the explosive particles based on CL-20/FOX-7 have better coating effect, and neither CL-20 nor FOX-7 has crystal transformation. The apparent activation energy of three kinds of PBXs are increased by 17.12, 32.87 and 40.24 kJ·mol^-1 compared with refined CL-20. The enthalpies of activation (ΔH) of PBX samples are also significantly improved compared with CL-20. The characteristic drop height increases from 27.5 cm of refine CL-20 to 58.3, 56.5 cm and 54.2 cm， respectively, compared with CL-20. The actual detonation velocities of three kinds of PBXs with different formulation proportions are 8474, 8503 m·s^-1 and 8577 m·s^-1 ，respectively, which is equivalent to the detonation velocity of PBXN-5, but the characteristic drop height increases by more than 48.5% compared with PBXN-5, the safety performance of explosives is significantly improved.