In a connector, a guide member to which an optical connector is fixed is provided with a first guide portion. The optical connector is provided with a second guide portion at a tip portion, in a mating direction, of a holding member thereof. The optical connector has a ferrule with a tip, and the tip is located between the first guide portion and the second guide portion in the mating direction. When the connector is connected to a structural body and before the optical connector reaches an accommodating portion, the first guide portion performs rough positioning of the optical connector with respect to the accommodating portion in a plane perpendicular to the mating direction. When the connector is connected to the structural body, the second guide portion guides the optical connector into the accommodating portion.