Abstract: A meso-numerical model was established to study the effects of RDX crystals and binders on the average mechanical properties of composite explosive 8701. The dynamic stress-strain curve of 8701 at strain rate 600/s was obtained by SHPB test.The macroscopic stress-strain curve was calculated according to the Tayler homogenization method.The results showed that the meso-numerical calculation model well describes the mechanical properties of 8701. Under high strain rate loading, the stress of RDX grain and binder increases with strain, but the strength and content of RDX are greater, so the mechanical properties of RDX grain play a leading role in the mechanical properties of 8701.