The invention provides a formula and method for preparing a three-dimensional-graphene coated single-particle nano-diamond material. According to the formula and the method, trinitrotoluene, cyclonite and metal are adopted as raw materials of the formula, and an energetic material is prepared from the raw materials of the formula, so that the three-dimensional-graphene coated single-particle nano-diamond material is synthesized by using high energy; and the formula provided by the invention is applied to a reaction method for the energetic material, substantial increase of cost is not caused compared with the traditional preparation processes, and enough high energy can be provided for the forming of the three-dimensional-graphene coated single-particle nano-diamond material, so that the three-dimensional-graphene coated single-particle nano-diamond material with relatively high purity is obtained.