The invention relates to an oil and electrical hybrid engine. The two ends of an air cylinder of the oil and electrical hybrid engine are provided with coil pistons capable of doing the linear reciprocating movement relative to the air cylinder. A combustion chamber is arranged between the two coil pistons. The two coil pistons are in sliding fit with the air cylinder. Wires are wound around the two coil pistons. Under the wire electrification state, the two coil pistons can get close to each other or get away from each other. The engine is provided with the changeable combustion chamber and the changeable air cylinder stroke and accordingly has efficient energy conversion and energy output, and the heat efficiency is greatly improved; and electric energy can be converted into mechanical energy. The acting processes of the hybrid engine are independent of one another, idle running is not needed, the starting process is not needed, and idling speed and starting process energy consumption can be reduced; and according to the different speeds, different transmission paths are selected, the maximum torque can be obtained within the limited speed range, power is improved through electric energy when power of an internal combustion engine is not enough, and excellent acceleration performance is achieved at the low speed and high speed.