Abstract: Provided is a device for observing and positioning a sharpening angle of a cutting edge. The device includes a spirit bubble for observing a change of a sharpening angle of a cutting edge and positioning the sharpening angle of the cutting edge, and a base for fixing the device on a knife body. The spirit bubble is rotatably connected to the base for adjusting an angle between the spirit bubble and the base. The device enables, in a dynamic process of grinding a cutting edge of a knife, a grinder to continuously remain in a correct sharpening angle range and grind the cutting edge in accordance with a correct sharpening angle of the knife when holding the knife to perform a grinding action, and also meets a requirement for controlling sharpening angles of cutting edges of knives with various edge shapes in respective edge grinding processes of the knives.