The invention provides a sealing tooth scraping tool which comprises a cutting tool, a drive unit and a positioning mechanism, wherein, the cutting tool is composed of a milling cutter and a group of cutter shafts, and the cutter shafts are equipped with upper locking nuts and lower locking nuts for adjusting the position of the milling cutter so that the cutting edge of the milling cutter corresponds to sealing teeth; the length of the cutter shafts changes in a constant gradient manner, the length gradient is equal to the distance between two adjacent rows of sealing teeth, and the cutter shafts are sequentially used for respectively machining the sealing teeth when in use; the positioning mechanism comprises a pair of depended wheels and a support; the support is provided with a horizontal plate and a vertical plate, and the bottom end surface of the vertical plate is a positioning datum plane; the depended wheels are distributed on the left side and right side of the vertical plate; the left depended wheel is fixed on a sliding seat; an adjusting screw is used for adjusting the distance between the sliding seat and the cutter shafts so as to determine the engagement of the milling cutter; the right depended wheel is fixed on a sliding block and is assembled on a sliding mechanism which is composed of a sliding rail, the sliding block and a screw rod; and the outside depended wheel is tightly attached to a workpiece by screwing the screw rod so that the dynamic relative position between the tool and the workpiece can remain stable.