The utility model discloses a stifled ware of silt is prevented to contrary formula of ending, top -down are in proper order including preventing the stifled ware cap that becomes silted up, upper and lower removable cover, the stifled ware main part of preventing becoming silted up, stay and clamping ring, the stifled ware main part of preventing becoming silted up is the tubular structure, and its lateral wall is provided with the apopore, removable cover can reciprocate from top to bottom. The utility model discloses with the ordinary lid that stifled ware of silt is prevented to contrary formula of ending replaces the check valve to push up, solved the technical problem that channel operation period check valve becomes silted up and blocks up, can ensure that the check valve effectively moves, guarantee channel operation safety. Stifled ware of silt is prevented to contrary formula of ending changes conveniently, and the accessory is changed easily, and maintenance cost is low. The desilting expense to the check valve can be practiced thrift, the normal operating of check valve can not be influenced to the canel desilting.