NOVELTY - The apparatus has a catalyst layer formation part (22) for forming a catalyst layer (12) on a side of a base material (21), where the catalyst layer contains catalyst and polymer electrolyte. A removal part (25) removes a protrusion part (13), which protrudes among catalyst layers formed by the catalyst layer formation part rather than a flat normal part, and making the catalyst layer to form as same film thickness of the normal part. A cooling part (27) cools the catalyst layer. A purity part (26) purifies a surface of the catalyst layer after removing the protrusion part.    USE - Apparatus for forming an electrode catalyst layer e.g. anode catalyst layer and cathode catalyst layer, that is utilized in a membrane/electrode joined body of a polymer electrolyte fuel cell (claimed) of an electric power generation system, which is utilized in a fixed-type cogeneration system, a power supply of a fuel cell electric vehicle and a domestic-use fixed power supply.    ADVANTAGE - The transfer of the catalyst layer is performed with respect to a polymer electrolyte membrane without causing damage to the polymer electrolyte membrane resulting from aggregation foreign material of a catalyst carrier in the catalyst layer of a catalyst layer sheet, or polymer electrolyte, foam and catalyst layer formation condition by the protrusion part, so that fall of battery characteristic can be prevented by the membrane/electrode joined body and durability of a battery can be improved. The cooling part cools the catalyst layer so as to prevent re-attaching of polymer electrolyte in removed aggregation foreign material on the catalyst layer. The apparatus is inexpensive.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a catalyst layer manufacturing method.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a catalyst layer forming apparatus.    Catalyst layer (12)    Protrusion part (13)    Base material (21)    Catalyst layer formation part (22)    Removal part (25)    Purity part (26)    Cooling part (27)