Electric storage device

There is provided an electric storage device having a novel fastening structure of a plastic member which can reduce cost with a simple configuration. An electric storage device according to this invention includes an electrode assembly, a case housing the electrode assembly, a plastic member arranged at an outer surface of the case, the plastic member having a joining surface facing the outer surface of the case, and an external terminal supported by the plastic member and electrically connected to the electrode assembly. The plastic member is a synthetic resin containing an inorganic fiber and is bonded to the outer surface of the case with the inorganic fiber exposed at the joining surface.