The present disclosure relates to a method for manufacturing an OLED light emitting device, an OLED light emitting device, and an OLED display device. The method for manufacturing an OLED light emitting device according to an embodiment of the present disclosure includes forming a pixel defining layer on a substrate, wherein the pixel defining layer comprises a lyophilic material or a lyophobic material and the pixel defining layer comprises a plurality of openings which are spaced apart from each other; forming an anode layer on the substrate and in each opening; adding a preset solvent having a property opposite to that of the lyophilic material or the lyophobic material of the pixel defining layer in an OLED film layer ink; and ink-jet printing the OLED film layer ink on the anode layer and in each opening to form an OLED film layer.