PURPOSE: To enable the sure surface protection of an optical fiber.

CONSTITUTION: An elastic body 31 is deformed by sliding contact with a pressing piece 18 to push down a detaining body 32 at the time of coupling both housings 11, 13. A guide pin 33 is moved upward by contact of an opening actuator 16 to rotate a hood body 28 in an exposing direction. The guide pin 33 is moved downward to rotate the hood body 28 in a coating direction by contact of a closing actuator so that the end face of the optical fiber 14 is coated and exposed by rotation of the hood body 28 at the time of separating the two housings 11, 13. Then, the end face of the optical fiber 14 is completely covered and protected. In addition, the elastic deformation of the elastic body 31 is prevented and the reliability of the end face protection of the optical fiber 14 is improved.