To figure out the coating mechanism of polymer bonded explosives （PBXs） prepared by spray drying and the effects of binders types and contents on the performance of PBXs， refined 1，1-diamino-2，2-dinitroethylene （FOX-7） and FOX-7 based PBXs with different binder types and contents were prepared by spray drying at the presence of poly ester urethane elastomer （Estane 5703）， fluororesin （F₂₃₁₄）， fluorine rubber （F₂₆₀₂） and acrylic rubber （ACM） as binders， respectively. The surface morphology， crystalline states ， thermal decomposition properties and impact sensitivity of the samples were characterized by field emission scanning electron microscopy （FE-SEM）， X-ray diffractometer （XRD）， differential scanning calorimeter （DSC） and impact sensitivity instrument， respectively. The results indicated that the crystalline state of the resulting samples was α-type. The FOX-7 based PBXs composited by Estane 5703 had the best sphericity， surface smoothness and mechanical safety， while the apparent activation energy decreased by 10.61%. The PBXs composited by F₂₆₀₂ exhibits satisfactory thermal stability. Both binders can effectively reduce the impact sensitivity of FOX-7. When the compounded binders containing Estane 5703 and F₂₆₀₂ at the mass ratio of 4∶1 content was 3%-5%， the surface of FOX-7-based PBXs particles is smooth and the adhesive effect is attractive. When the compounded binder content was 5%， the resulting FOX-7-based PBXs possess excellent safety performance. The compositing structure and desensitization mechanism of binders in PBXs obtained by spray drying were analyzed from the microscopic morphology of FOX-7 in molten state. And the comparative analysis of impact sensitivity， atomic ratio of surface elements and chemical state changes between refined FOX-7 and resulting PBXs was carried out to verify them.