Optical fibers can have a low-loss connection with each other, and laser light can be stably guided. Plug side optical fibers (55) are held by a plug side holder (105) and receptacle side optical fibers (99) are held by a receptacle side holder (107). The receptacle side holder (107) is supported, by means of a holder aligning means (113), so as to be able to move in parallel in a direction which is perpendicular to a connector bonding direction (a). When the receptacle and the plug are connected, the receptacle side optical fibers (99) in the receptacle side holder (107) and the plug side optical fibers (55) in the plug side holder (105) are aligned by means of the holder aligning means (113).
