A
bus wiring plate body (20), for an
electric coupling box, is arranged in a manner that
bus bar members (23, 24) are wired between pre-hardening
epoxy resin plates (21, 22) and these pre-hardening
epoxy resin plates are subjected to a heat pressing process to thereby integrate the pre-hardening
epoxy resin plates (21, 22) and the
bus bar members (23, 24) in a laminated state. When hardened epoxy resin plates (25, 26) are disposed outside of the pre- hardening epoxy resin plates (21, 22), respectively, the strength of the bus bar wiring plate body (20) can be improved. Thus, since the bus bar members (23, 24) are sealed in an insulated state, leak current is reduced. Further, the thickness of the bus bar wiring plate body (20) is reduced to a large extent, so that the
electric coupling box can be miniaturized and lightweighted.