A connector 10 disclosed by this specification includes a housing (retainer 30), and a cover 50 to be attached to the housing from behind. The cover 50 includes an opening 57 open in a direction intersecting an attaching direction to the housing, a facing portion 58 facing the opening 57, an outer lock portion 55 provided at least on the facing portion 58 and an inner lock portion 54 provided adjacent to the outer lock portion 55. The housing includes an outer lock receiving portion 36 to be locked in a separating direction of the cover 50 by the outer lock portion 55 coming into contact therewith from an outer peripheral side and an inner lock portion 35 to be locked in the separating direction of the cover 50 by the inner lock portion 54 coming into contact therewith from an inner peripheral side.