The present invention relates to a polygon rotatable razor blade, which is arranged with cutting edge (2) extending with linear mode or curve mode within a plane being vertical to locating surface (1), and the cutting edge (2) descends from a acute cutting knifepoint (3) to a cutting knifepoint (4) with obtuse angle alternating with the cutting knifepoint (3). The cutting edge (2) is arranged with front chin surface (6) which descends firstly and ascends in the back area (7). The back area (7) forms intersecting curve (8) with the central part (18) of the rotatable razor blade. In the cuttingknifepoint (3) area, the distance between the intersection point (9) of the intersecting curve (8) and angular bisector (10), and the beginning point (15) of the cutting edge (2) is always a. In the cutting knifepoint (4) area, the distance between the intersection point (11) of the intersecting curve (8) and angular bisector (12), and the end point (16) of the cutting edge (2) is always b, and bis above a.