The invention discloses an alcohol-hydrogen mixed fuel power system. The alcohol-hydrogen mixed fuel power system comprises an alcohol box, an evaporator, an electrolyzer and an engine. An inner cavity of the evaporator communicates with a tail gas exhausting pipe of the engine. The alcohol box is connected with one end of a pipeline of the inner cavity of the evaporator through a delivering pipe. An alcohol pump is installed on the delivering pipe of one end of the alcohol box. The other end of the pipeline of the inner cavity of the evaporator is connected with one end of the electrolyzer. The other end of the electrolyzer is connected with a fuel gas nozzle in the engine through a fuel delivering pipe. A storing tank is installed on the fuel delivering pipe. A compressor and a cooling tank are installed on the fuel delivering pipe between the storing tank and the electrolyzer in sequence. A flowmeter and an electromagnetic valve are installed on the delivering pipe between the alcohol pump and the evaporator in sequence. A cathode plate and an anode plate connected with a battery and a controller are installed in the electrolyzer. The alcohol-hydrogen mixed fuel power system is reasonable in structure, convenient to install and operate and high in intelligent degree, hydrogen is prepared by using alcohol pyrolysis to be supplied to the engine to be used, long-time stable working of a device is ensured, and waste gas pollution of current gasoline cars is reduced.