Manhole waterproof tool

The invention discloses a manhole waterproof tool which comprises a base and a cover body. The base is of a C-shaped structure. The base comprises a base plate, a surrounding plate, a magnetic sealinggasket, a sealing ring and a U-shaped connecting piece; the inner edge of the base plate is fixedly connected with the lower edge of the surrounding plate; an annular embedding groove is formed in the lower end face of the base plate; the magnetic sealing gasket is located in the annular embedding groove; a positioning through hole is formed in the position, outside the annular embedding groove,of the base plate; the surrounding plate is sleeved with the sealing ring; the lower end face of the sealing ring is connected with the upper end face of the base plate, and the U-shaped connecting piece is connected to the opening of the C-shaped surrounding plate in a sleeving manner. The tool is simple in structure, good in waterproof effect and simple in mounting method and operation step; theerror between the actual s