Abstract: To improve the solid content of casting explosive based on RDX, the spherical RDX was prepared by recrystallization using Cyclohexanyne as a solvent. The influence of crystallization temperature, stirring speed and impurity on RDX crystal shape was analyzed. The crystal shape, free-flowing property, impact sensitivity and friction sensitivity of both spherical RDX and ordinary RDX were tested. Spherical RDX and ordinary RDX were used to prepare PBX with the same casting formula and their shock sensitivity was tested, respectively. The results show that the crystal shape of spherical RDX is regular, the surface is sleek and lack of edge angle. Spherical RDX has better free-flowing property than ordinary RDX. The impact sensitivity and friction sensitivity of spherical RDX are lower than ordinary RDX. PBX shock sensitivity based on spherical RDX is 25% lower than based on ordinary RDX.