An energy-saving brushless motor-kinetic generator is provided in the present invention, especially a combination structure by adjusting the rotors and the stators in the electric generator. The energy-saving brushless motor-kinetic generator with the new combination structure can be simply cascaded to assemble an energy-saving system with the energy-saving brushless motor-kinetic generator included with magnetic energy motor electric power. The energy-saving brushless motor-kinetic generator can specifically perform transformation of magnetic energy and mechanical energy by magnetic energy of permanent magnet of the rotors and design of turns of the stator windings, so to enhance output of electrical energy.