Abstract: A connector which includes a connector socket and a mated connector plug to be fitted into the connector socket has a socket body which includes upper and lower terminal holding portions. The upper and lower terminal holding portions each have a plurality of terminals which are arranged in a row along the width direction of the socket body. The upper and lower terminal holding portions are arranged so as to face each other through a predetermined spacing. The connector socket further has a rib for maintaining the spacing between the upper and lower terminal holding portions for preventing both the terminal holding portions from being deformed so that they approach each other. The rib is integrally formed with the upper and lower terminal holding portions and arranged substantially at the center of the width direction of the socket body. The mated connector plug has a plate member which is inserted into the spacing when the connector plug is connected to the connector socket.