The invention relates to a device for driving multiple rotors of an airplane, which comprises a main differential mechanism driven by an engine, auxiliary differential mechanisms which are installed on the main differential mechanism and driven by a main driving shaft, and auxiliary driving shafts which are installed on both sides of each auxiliary differential mechanism, wherein the other end of each auxiliary driving shaft is provided with two bevel gears which mesh with each other and are used for driving the rotors. By using one engine to drive the rotors, the device can lower the manufacturing cost; and the engine can adopt a fuel engine, thereby solving the problems of poor loading capacity, short flight duration and the like in the electric multi-rotor aircraft.