Methods of fabricating an OLED and a donor substrate are provided. The method includes: preparing a base substrate of a donor substrate; forming a light to heat conversion layer and a transfer layer on the base substrate; preparing a donor substrate including performing a dry cleaning process after forming the transfer layer; preparing a substrate, on which the transfer layer of the donor substrate is to be transferred; laminating the donor substrate and the substrate; and patterning the transfer layer by irradiating a laser to transfer the transfer layer on the substrate.