There are provided a pattern exposure method, a conductive film producing method, and a conductive film, wherein a photosensitive material is subjected to a proximity exposure through a photomask disposed with a proximity gap of 70 to 200 μm, and thereby is exposed in the mask pattern periodically in the conveying direction to obtain a conductive film. The conductive film has a plurality of conductive portions of first and second conductive thin metal wires and a plurality of opening portions. A side of each thin metal wire has a protrusion extending toward the opening portion from a virtual line representing a designed width of the thin metal wire, and the protruding amount of the protrusion is 1/25 to 1/6 of the designed width.