The invention relates to a spiral plate engine, which mainly comprises an air compressor, a power machine, a baffle plate and a magneto igniter. The main bodies of the air compressor and the power machine consist of stators, rotors in the stators, and spiral plate devices on the rotors. The rotor of the air compressor and the rotor of the power machine are coaxially arranged in series; a rear spindle head of the air compressor extends out of a bearing block of a back end cover to connect with the magneto igniter; a shaft joint between the air compressor and the power machine is arranged in a shaft hole of the baffle plate; and a power spindle head of the power machine extends out of a bearing block of a front end cover to apply work to the outside. The stator of the air compressor and the stator of the power machine are connected with each other through flanges, and the baffle plate is clamped between the two flanges. The compressed air generated by the air compressor is delivered to the power machine through a compressed air passage. The spiral plate engine is simple in structure, easy to manufacture and low in cost, is convenient to operate and maintain, is not provided with a reciprocating part, generates light vibration and low noise, is widely suitable for a variety of means of communication such as automobiles, ships, planes and the like, and is an engine of new generation for replacing a piston engine.