A connector includes a first housing and a second housing to be connected to each other, and a connection assisting member to be mounted into the first housing. The connection assisting member includes a cam groove extending from an entrance to a back end. The cam groove has a connection cam surface to be pushed by a cam pin in a connecting direction of the first housing and a recess connected to an end part of the connection cam surface on the side of the back end and recessed more in the connecting direction than the end part of the connection cam surface on the side of the back end. The cam pin located on the side of the back end of the cam groove is arranged not to contact an inner surface of the recess with the first and second housings connected to each other.