A connector (1) includes a connector housing (2), a terminal (3) received in a terminal reception chamber (21), and a retainer (4) inserted in a retainer insertion hole (22) of the connector housing (2) and configured to shift between a terminal insertion allowable position and a terminal fit position. A terminal locking protrusion (47) of the retainer (4) has a base protrusion (45) configured to come in contact with a rear wall (31b) of an opposite terminal connection part (31) of the terminal (3) with the retainer (4) being in the terminal fit position, and a tip end protrusion (46) provided on an enter-side face of the base protrusion (45) and configured to enter space inside a connection part (33) of the terminal (3) with the retainer (4) being in the terminal fit position.