To provide an underwater sailing device which is used during cleaning of a fish net for breeding, and is formed in such a manner that a propeller having an axis pointing to a vertical direction is arranged at a body having a traveling means to move a body, and the propeller is ratated by a drive means arranged at the body.

When a underwater sailing device is applicable for an underwater cleaning device used during cleaning of a fish net for breeding, tires 2 driven and rotated by a servo motor 3 are arranged at the four corners of a body 1. A jet nozzle 4 is arranged on the under surface of the body 1 and a propeller 5 having an axis pointing to a vertical direction is rotatably arranged at the upper part. A propeller 5 is rotated by a three-phase induction electric motor 6 and the rotation direction thereof is varied. Further, a pair of guide bars 11 are arranged on the upper surface of the body 1 and the end parts of a wire 12 extending through a floater 13 are respectively fixed. By moving the floater 13 along the guide bar 11 through regulation of the wire 12, the buoyancy center position of a device is regulatable.