The utility model discloses a universal navigation buoy with adjustable buoyancy. Marine buoy comprising a marine buoy body, an anti-collision mechanism is fixedly installed on the outer surface of the navigation buoy body. A buoy floating device is fixedly mounted on the outer surface of the lower end of the navigation buoy main body; a balance weight connecting rod is fixedly installed on the outer surface of the lower end of the buoy floating device, a replaceable balance weight block is fixedly installed on the outer surface of the lower end of the balance weight connecting rod, and a supporting rod, a pull wire containing box and a connecting fixing rod are fixedly installed on the outer surface of the upper end of the navigation buoy body. The utility model relates to a universal navigation buoy with adjustable buoyancy. The light-reflecting rotating hemisphere, the supporting fence and the replaceable balancing weight are arranged, so that birds can be prevented from falling onthe solar storage battery, people can maintain the navigation buoy conveniently, the buoyancy of the buoy can be changed, the gravity center position of the buoy is not changed, the stability of the buoy is guaranteed, and a better use prospect is brought.