The invention relates to the field of manufacturing of cables with complex structures, and provides a method for preparing a 3D printing electric wire and cable. A finished cable is manufactured by inputting a three-dimensional cable structure in software of a 3D printer according to each layer structure of the cable, and using corresponding cable materials to obtain the cable by a fused deposition forming technology in the 3D printing technology. The 3D printing technology is introduced into cable manufacturing, the production of wire and cable products is more accurate, the appearance is more attractive, the unqualified quality of the cable products due to errors in the production process and introduction of impurities in the production process can be avoided, and a lot of labor cost, material cost and mechanical cost can be saved for complex cables such as umbilical cables, submarine cables and the like high in process requirement and large in length.