Abstract: In a fiber-gripping device has a gripper head provided with a V-groove for housing an optical fiber and an elastically deformable holding member which is brought to bear on the optical fiber. The gripper head and holding member are provided with V-section channels located respectively in oppositely-facing relation. A cylindrical rod forming a pivot-pin is placed between said oppositely-facing channels. The device is caused to open by a spring which tends to produce a movement of pivotal displacement of the holding member away from the gripper head. A locking lever is adapted to move into a first position in which the holding member is located at a sufficient distance from the gripper head to permit free passage of the optical fiber and a second position in which the holding member fixes the optical fiber within its V-groove and exerts a force which is controlled by its own elastic deformation.