A connector includes a housing (20) and a front retainer (40) to be mounted into the housing (20) from the front. The housing (20) includes locking lances (31) for locking terminal fittings (10) inserted to proper positions. The locking lance (31) is pressed by the terminal fitting (10) and retracted into a deflection space (S1) when the terminal fitting (10) is inserted, and resiliently returns and locks the terminal fitting (10) when the terminal fitting (10) is inserted properly. The front retainer (40) includes deflection restricting portions (42) for restricting deformation of the locking lances (31) by entering the deflection spaces (S1), and includes ribs (45) that can contact and guide a tip of a tab (11) if the tab (11) is inclined during insertion of the terminal fitting (10).