It is disclosed a photosensitive resin composition comprising (a) a binder polymer based on a copolymer containing benzyl (meth)acrylate as a building block, (b) a photopolymerizable compound having at least one polymerizable ethylenically unsaturated group in the molecule and (c) a photopolymerization initiator based on a hexarylbisimidazole compound, with a light-initiated color former being optionally contained as component (d). The composition has long-term keeping quality, exhibits particularly high resistance to plating and dry etching, as well as assuring improvement in resolution and adhesion; the composition may be used to form a photosensitive dry film.