The invention relates to a self power generation type engine flywheel device, and belongs to the technical field of automobile engines. The invention aims to make use of a coil on the flywheel and anelectromagnet beside the flywheel to form a power generation system. When a driver brakes, the electromagnet is electrified and produces a magnetic field, the rotating flywheel drives the coil to cuta magnetic induction line in the magnetic field to generate power, at the same time, the resistance of the magnetic field to the coil plays a certain deceleration role to the flywheel. When an automobile starts up, the electromagnet and the coil are electrified simultaneously to produce two magnetic fields, the magnetic force between the two magnetic fields enables the coil to participate in the flywheel starting process and reduces the load of a starting motor. The electric energy generated in the flywheel power generation process is transmitted to the super capacitor for storage through a wireless electric transmission device. The super capacitor provides the electric energy needed by the coil when the vehicle starts up. A pedal dynamometer solves the problem of detecting the braking force. The engine flywheel can reduce the loss of the engine flywheel and the starting motor, and the surplus kinetic energy of the flywheel is used for generating power, and the self power generation type engine flywheel device is superior to a traditional engine flywheel.