To provide a group III nitride semiconductor light-emitting element manufacturing method excellent in manufacturing efficiency.

The group III nitride semiconductor light-emitting element manufacturing method comprises: an element formation step of preparing a single crystal substrate containing an impurity of 30 ppm and over as a single crystal substrate, laminating an intermediate layer of a group III nitride semiconductor in contact with a principal surface of the single crystal substrate by a sputtering method and subsequently forming a laminated semiconductor layer so as to cover the intermediate layer; a laser processing step of forming processed marks inside the single crystal substrate by condensing laser beams having a wavelength that causes photoexcitation with respect to an impurity level of the single crystal substrate to the inside of the single crystal substrate along scheduled cutting lines for dividing the single crystal substrate into a plurality of chips; and a division step of dividing the single crystal substrate along the processed marks and the scheduled cutting lines to obtain the plurality of chips.