The invention relates to a solid motor nozzle blank assembly. The solid motor nozzle blank assembly is characterized in that the solid motor nozzle blank assembly is composed of a guide ring blank, aheat insulation body and a nozzle body blank; the outer surface of the heat insulation body is consistent with the inner surface of the nozzle body blank, and the diameter of the lower section of theinner surface of the heat insulation body is the same as that of a positioning step hole; the upper end of the heat insulation body is consistent with the outer surface of the guide ring blank, and the portion, between the end surface of the positioning step hole and the small end surface of the guide ring blank, of the inner surface of the heat insulation body is in a continuous and smooth trumpet shape from small to large; and the material of the heat insulation body is a high silica cloth/phenolic aldehyde combination, the forming pressure ranges from 20 MPa to 28 MPa, the materials are placed on an oil press equipped with upper and lower heating plates and is heated to 160-170 DEG C, the heat is preserved and the pressure is maintained for 8-10 minutes, and then a mold is removed. According to the solid motor nozzle blank assembly, the surface of a nozzle body is covered with a layer of heat insulation body with ablation resistance and good heat insulation performance, so that thedefect that the inner wall of a solid motor nozzle is likely to be ablated under the action of high temperature of tail gas is overcome, and the service life of the solid motor nozzle is prolonged.