The present invention provides a method for bonding a membrane electrode assembly (MEA) and a gas diffusion layer (GDL) of a fuel cell stack, which facilitates stacking of an electrode catalyst layer of the MEA and the GDL and, at the same time, facilitates the keeping of the stacked layers for mass production of the fuel cell stack.For this purpose, the present invention provides a method for bonding a membrane electrode assembly and a gas diffusion layer of a fuel cell stack, the method including: coating a catalyst layer on a surface of a polymer electrolyte membrane; attaching a sub-gasket on the circumference of the polymer electrolyte membrane; and stacking a gas diffusion layer onto an outer surface of the catalyst layer by bonding all or a portion of an outer surface of the sub-gasket and the circumference of the gas diffusion layer with a bonding means.