The application discloses a reamer, which is characterized by comprising a cutter head and a cutter handle, wherein the cutter head and the cutter handle are connected; the cutter head is a flat cuboid cutter head; cutting edges are formed on the four edges of the flat cuboid cutter head; and the profile of the cutting edges are arc shaped. The cutter head disclosed by the application adopts double-side and four-edge design, has a plurality of cutting edges, improves reaming efficiency and makes the reaming more smooth and soft; the arc-shaped cutting edge profile design makes the sheaving more fit with the physiological curvature of the end plate of the human body, reduces ineffective damage, accelerates scraping end plate graft bed forming, and contributes to the fit between the implanted material and the end plate to make the implanted material supported stably; and the arc-shaped cutting edge profile makes the glue scraping part more smooth and uniform.