The utility model relates to a conjoined water-cooling device laser-cladding head for restoring a drilling-platform lifting gear, which comprises an optical-fiber inlet, an optical-cavity main body, a water-pipe interface, a water-cooling device, a locknut and a light outlet; the optical-fiber inlet is arranged above the optical-cavity main body, the water-cooling device is arranged below the optical-cavity main body, and the water-cooling device is connected with the water-pipe interface; the water-cooling device and the light outlet are fixedly connected by adopting the locknut; and the optical-cavity main body as well as the optical-fiber inlet and the light outlet which are correspondingly arranged above and below the optical-cavity main body are concentrically arranged. In order to ensure the production quality and the equipment safety, the water-cooling device is independently arranged at the part at the lower end of the cladding head in the structural design close to the light outlet, i.e. a waterway is added above the light outlet to cool the light outlet. The cladding head has the advantages of simple structure, reasonable design, convenience in operation and reliable safety performance, and not only is the stable operation of processing equipment effectively ensured, but also the quality of a processed product can be improved, the processing efficiency is improved, and the application range is wide.