The invention relates to a top conversion tool used for preventing sand. The top conversion tool used for preventing the sand is characterized in that a machinery hand releasing tool, a rotating connector tool, module sealing units, a top circulation nipple, a central pipe X-over, an oil pipe nipple and a washpipe X-over are included, the lower portion of the machinery hand releasing tool is connected with the rotating connector tool, the lower portion of the rotating connector tool is connected with the top circulation nipple, the lower portion of the top circulation nipple is connected with a plurality of module sealing units, the bottom of each module sealing unit is connected with the washpipe X-over, and the central pipe X-over is connected inside the machinery hand releasing tool. The machinery hand releasing tool comprises an upper connector, a righting ring, a mandrel, a square buckle nipple and a lower mandrel. The rotating connector tool comprises an upper connector, a setting cylinder, a mandrel and a lower connector. Each module sealing unit comprises a sealing module, a sealing ring and a module nipple. The top conversion tool used for preventing the sand has the advantages of being capable of achieving that an outer layer anti-sand tool can be reliably connected into a well and can be effectively and smoothly released from a hand, avoiding rotating friction caused by an overlong tubular column, greatly reducing field operation risks and achieving gravel filling work and reverse circulation work by being matched with the outer anti-sand tubular column.