An object of the present invention is to provide a method for producing a p-type Group III nitride semiconductor which can be used to produce a light-emitting device exhibiting a low operation voltage and a sufficiently high reverse voltage.The inventive method for producing a p-type Group III nitride semiconductor comprises, during lowering temperature after completion of growth of a Group III nitride semiconductor containing a p-type dopant, immediately after completion of the growth, starting, at a temperature at which the growth has been completed, supply of a carrier gas composed of an inert gas and reduction of the flow rate of a nitrogen source; and stopping supply of the nitrogen source at a time in the course of lowering the temperature.