Cutting blade special for backboard cutting machine

The utility model relates to a cutting blade special for a backboard cutting machine. The cutting blade comprises a blade body (1), wherein the whole blade body (1) is in a trapezoid shape and is provided with a cutter back (2), cutting edges and an installation hole (5). The cutting edges are divided into the inclined cutting edge (3) and the perpendicular cutting edge (4), wherein the included angle alpha between the inclined cutting edge (3) and the perpendicular cutting edge (4) ranges from 70 degrees to 75 degrees, and the distance W between the cutting edge tip (6) of the joint of the inclined cutting edge (3) and the perpendicular cutting edge (4) and the edge of the cutting edge of the perpendicular cutting edge (4) is 3 mm. By means of the cutting blade, cutting knife edges of backboards are located on the same straight line, the requirement for the cutting accuracy is ensured, notches of various specifications can be obtained through cutting without replacing design or cutters, the switching and cutting of backboard sheets of various specifications are flexibly achieved, and the production efficiency is greatly improved.