The invention discloses a municipal sewer dredging device. The municipal sewer dredging device comprises a moving seat, a first motor, a water pump, a ball, a first metal hose, a water pumping pipe, afixing device and a second metal hose; and a main shaft is arranged on the middle part of the moving seat, a large rotating tube and a small rotating tube are arranged on the outer side of the main shaft separately in a bolted mode, the first motor bolt is mounted on the inner right side of the moving seat, the ball is disposed below the large rotating tube, a drill bit is arranged on the left side of a steel rope, and the fixing device is disposed on the middle part of the steel rope. The municipal sewer dredging device is provided with the drill bit, a second motor drives the conical drillbit and a drill pipe to rotate, obstruction can be effectively subjected to punching, meanwhile, an internal rolling bearing, a first baffle block, a second baffle block and a through hole effectivelyprevent the movement of an inner fixed shell, the normal operation of the drill bit is ensured, and the use of the first motor and the large rotating tube and the small rotating tube is matched to provide propulsion force for the drill bit.