A fabrication method of a patterned metal film layer, including: sequentially depositing a first metal layer and a photoresist on a substrate; forming a first patterned photoresist in the photoresist retaining area; etching the first metal layer, and removing a part of the first metal layer having a first thickness and located in an edge area of the photoresist retaining area and in the photoresist removing area, to form a second metal layer; processing the first patterned photoresist to form a second patterned photoresist; etching and removing a part, which is not in contact with the second patterned photoresist, of the second metal layer on the substrate to form a patterned metal film layer.