The invention provides a deconcentrator with
optical fiber crossing and
loopback functions, and relates to the technical field of optical cable joints, the deconcentrator comprises a
fiber distribution box and a cover plate, the two ends and the top of the
fiber distribution box are opened, the top of the
fiber distribution box is provided with the detachable cover plate, a plurality of fiber winding columns are arranged in the fiber distribution box, and the fiber winding columns are arranged according to a set arc path. An
optical fiber loopback channel is formed between the plurality of fiber winding columns and the box walls of the fiber distribution boxes on the two sides, an installation channel used for installing a strip-shaped crossed
optical fiber is formed between the openings in the two ends of each fiber distribution box and the plurality of fiber winding columns, an
insertion hole is formed in the cover plate, and when the cover plate covers the top of each fiber distribution box, the fiber winding columns penetrate into the
insertion holes. The deconcentrator can realize the cross
interconnection and
loopback functions of the optical fibers, and solves the problems in the prior art that the bending
radius of the optical fibers is too small and the optical fibers are pressed to cause breakage.