A ferrule holding member has a tube-shaped receiving portion including a receiving space therein, the receiving space receiving at least partially a ferrule mounted to a terminal of an optical fiber; and an engaging portion engaged to the ferrule received in the receiving portion, to thereby regulate movement of the ferrule relative to the receiving portion. The receiving portion includes a communicating hole to allow the receiving space to communicate externally. The engaging portion includes an engaging protrusion configured to be inserted in the communicating hole from an outer periphery side of the receiving portion, to engage the ferrule.