A hybrid combustion apparatus using pyrolysis of water and combustion air, the hybrid combustion apparatus characterized by comprising: a combustion unit configured such that a housing thereof is formed such that a center portion of the housing in a vertical direction is formed in a column shape and top and bottom surfaces thereof are inclined, and further configured such that a waste stowage support configured such that waste introduced through a waste introduction inlet is stacked thereon while being rotated by driving of a rotational drive device is provided inside the housing; an ignition unit installed through a top surface of the combustion unit, and configured to ignite waste; a primary combustion chamber defined by a double wall including an outer shell and an inner shell, installed above the combustion unit, and formed to have a diameter smaller than that of a column portion of the combustion unit; a primary combustion chamber air blower configured to feed combustion air from one side of a lower end portion of the primary combustion chamber to a gap of the double wall of the primary combustion chamber through a combustion chamber air feed path; a secondary combustion chamber defined by a double wall including an outer shell and an inner shell, installed above the primary combustion chamber, and configured such that an exhaust outlet configured to discharge exhaust gas is formed through one side of an upper end portion of the secondary combustion chamber; a shaftless screw pipe formed as a pipe in a column shape whose lower end is closed, vertically installed along inner center portions of the primary and secondary combustion chambers (12, 13) from an upper end portion of the secondary combustion chamber to an upper end portion of the primary combustion chamber, configured such that a plurality of holes is formed at equal intervals in a portion of the shaftless screw pipe located in the primary combustion chamber, and provided therein with a shaftless screw; a secondary combustion chamber air blower configured to feed combustion air from one side of a lower end portion of the secondary combustion chamber through a gap of the double wall of the secondary combustion chamber to the shaftless screw pipe via an air blowing pipe; and a high-frequency induction heating furnace provided at a lower end of the combustion unit, and configured to melt combustion ash discharged after combustion and process the ash into slag; wherein a ring-shaped blocking plate having a predetermined width is installed at an upper end of the primary combustion chamber, a ring-shaped inner end of the blocking plate is vertically bent downward and forms an exhaust outlet vertical wall, and a lower end portion of the shaftless screw pipe is located inside the exhaust outlet vertical wall. a combustion unit configured such that a housing thereof is formed such that a center portion of the housing in a vertical direction is formed in a column shape and top and bottom surfaces thereof are inclined, and further configured such that a waste stowage support configured such that waste introduced through a waste introduction inlet is stacked thereon while being rotated by driving of a rotational drive device is provided inside the housing; an ignition unit installed through a top surface of the combustion unit, and configured to ignite waste; a primary combustion chamber defined by a double wall including an outer shell and an inner shell, installed above the combustion unit, and formed to have a diameter smaller than that of a column portion of the combustion unit; a primary combustion chamber air blower configured to feed combustion air from one side of a lower end portion of the primary combustion chamber to a gap of the double wall of the primary combustion chamber through a combustion chamber air feed path; a secondary combustion chamber defined by a double wall including an outer shell and an inner shell, installed above the primary combustion chamber, and configured such that an exhaust outlet configured to discharge exhaust gas is formed through one side of an upper end portion of the secondary combustion chamber; a shaftless screw pipe formed as a pipe in a column shape whose lower end is closed, vertically installed along inner center portions of the primary and secondary combustion chambers (12, 13) from an upper end portion of the secondary combustion chamber to an upper end portion of the primary combustion chamber, configured such that a plurality of holes is formed at equal intervals in a portion of the shaftless screw pipe located in the primary combustion chamber, and provided therein with a shaftless screw; a secondary combustion chamber air blower configured to feed combustion air from one side of a lower end portion of the secondary combustion chamber through a gap of the double wall of the secondary combustion chamber to the shaftless screw pipe via an air blowing pipe; and a high-frequency induction heating furnace provided at a lower end of the combustion unit, and configured to melt combustion ash discharged after combustion and process the ash into slag; wherein a ring-shaped blocking plate having a predetermined width is installed at an upper end of the primary combustion chamber, a ring-shaped inner end of the blocking plate is vertically bent downward and forms an exhaust outlet vertical wall, and a lower end portion of the shaftless screw pipe is located inside the exhaust outlet vertical wall.