Disclosed is a duct piece infiltration detector for shields. A support is arranged below an arc plate which is provided with a water inlet hole. The water inlet hole is connected with a water pump, and a duct piece to be detected is disposed above the arc plate. A sealing frame is arranged between the arc plate and the duct piece to be detected and made of rubber. The water pump is provided with a pressure gauge. Infiltration of the duct piece can be detected by the duct piece infiltration detector, and quality thereof can be evaluated reasonably. The problem that infiltration of the duct piece during shield construction is not easy to be measured is effectively solved. In addition, the duct piece infiltration detector for shields is simple in structure, convenient to operate and easy to be popularized in shield construction.