The present invention is intended to provide a hybrid combustion apparatus using the pyrolysis of water and combustion air, in which a combustion chamber is defined by a double wall and divided into a primary combustion chamber configured to combust waste and a secondary combustion chamber configured to combust exhaust gas, and the size (diameter) of a combustion unit through which waste is configured to be different from that of the combustion chamber in which a flame is located, so that combustion temperature is further increased by introducing air, so that heated due to proximity to a flame, as combustion air, combustible waste is combusted at an ultrahigh temperature by pyrolyzing water and combustion air by means of a high combustion temperature, and so that complete combustion is achieved by increasing the time for which a flame stays within the combustion chamber, thereby discharging clean exhaust gas.