The invention discloses a mechanical-electricity binary power engine and relates to the field of internal combustion engine engineering. The mechanical-electricity binary power engine comprises a piston, an electromagnetic coil, a sliding electric brush and a connecting rod body. Elastic retaining rings installed in an embedding groove in a pin hole of the piston are arranged at the two ends of apiston pin; an annular groove is formed in the skirt section of the piston, and the electromagnetic coil is arranged in the annular groove; the sliding electric brush makes close contact with electricbenign conductor pole pieces through compressing springs; and when the piston makes reciprocating movement in a cylinder sleeve, the electromagnetic coil in the piston makes movement of cutting the magnetic induction line between two magnets, and the piston, the electromagnetic coil and the sliding electric brush make synchronous movement. The mechanical-electricity binary power engine has the beneficial effects that heat energy is converted and output into mechanical energy and hydraulic energy simultaneously; the coil serves as a rotor, and the magnets serve as a stator, so that the structure is simplified; the situation that the piston pin moves in the piston and scrapes the air cylinder sleeve is reduced; transmitting is stable, increasing of the height and the reciprocating inertia of an engine body is little, working is stable, adaptability is high, the energy conversion efficiency is high, and the technical inheritance property is good; and great application and popularizationvalue is achieved.