Within a resin mold portion of a fuel injection valve, an amplifying member having a substrate is provided. An engagement hole that penetrates in an axial direction is formed in another end part of the amplifying member, and an engagement pin, which is formed on a bobbin of a housing, is inserted through the engagement hole. A second connector of a second signal transmitting member, which constitutes part of a signal transmitting unit, is inserted from below into a connecting hole formed in the substrate. In addition, when the resin mold portion is molded, the amplifying member is retained in a state with the engagement pin and the second connector being inserted, respectively, into the engagement hole and the connecting hole.