The invention provides a head structure for a generator and an assembly method for the head structure. The head structure for the generator comprises a head body, a combustion nozzle and an ignition electrode, wherein a nozzle channel and an ignition electrode channel are formed in the head body; the combustion nozzle is arranged in the nozzle channel and is provided with a nozzle body; a fuel inlet and a pure oxygen inlet are formed in one end of the nozzle body; a plurality of diaphragm outer cavities are formed in the other end of the nozzle body; a fuel channel which communicates with the fuel inlet is formed in the nozzle body; the other end of the fuel channel communicates with the plurality of diaphragm outer cavities through a plurality of fuel inclined holes; the fuel inclined holes are radially formed in an outward inclined manner in the spraying direction of fuel; a pure oxygen channel which communicates with the pure oxygen inlet is also formed in the nozzle body; the other end of the pure oxygen channel communicates with the plurality of diaphragm outer cavities through a plurality of pure oxygen inclined holes; the pure oxygen inclined holes are radially formed in an inward inclined manner in the spraying direction of pure oxygen; and the ignition electrode is arranged in the ignition electrode channel. The head structure for the generator resists high temperature and oxidation, has a safe and reliable structure and is long in service life.