The utility model provides a hydraulic concrete member expansion joint water-stop belt connecting structure which comprises a protection layer and a sealing padding layer. The sealing padding layer is put into an expansion joint at a damaged part of a water-stop belt in a filling mode, and the protection layer covers the sealing padding layer and the outer side of the end of the damaged part of the water-stop belt and is combined with the end. The sealing padding layer can well seal a joint opening of the damaged part and can provide support needed by the protection layer. The protection layer can be directly formed through the mode of smearing a flexible film material on site, and thus the protection layer can be directly and tightly combined with the end of the water-stop belt. It is the best that an activating agent and a binder are brushed between the protection layer and the water-stop belt. The problem of connection of the damaged part of the hydraulic concrete member expansion joint water-stop belt is solved, and compared with a conventional mode of the technology that the water-stop belt is removed and replaced, the hydraulic concrete member expansion joint water-stop belt connecting structure is simple and easy to achieve, and the performance of the connected water-stop belt is good.