The invention provides a rotary blade with a jagged self-sharpening coating. A plurality of blade teeth are arranged at a blade part of the rotary blade at intervals; the blade teeth are made of self-sharpening coatings; each of the self-sharpening coatings is prepared in the following steps: mixing and stirring tungsten carbide powder, nickel-based solder powder and ethyl cellulose, kneading, pressing and rolling the mixture to obtain an adhesive tape solder and cutting the adhesive tape solder into flake-like solders for standby application; pasting one flake-like solder in the length direction of the blade part every other distance until the flake-like solders are arrayed on a working face of the whole rotary blade; placing the rotary blade with prearranged flake-like solders into a drying oven for drying; fixing the rotary blade in a protective air room with clamps and rapidly scanning the flake-like solders by taking CO2 laser spots as heat sources; melting the flake-like solders,spreading the melt flake-like solders and completing metallurgical bonding of the melt flake-like solders and the rotary blade, so as to obtain the rotary blade with the jagged self-sharpening coating. The rotary blade with the jagged self-sharpening coating is better in self-sharpening and longer in service life; in addition, the laser spots are adopted as the heat sources, so that the heating rate is high, a heat affected zone of a parent metal is small, and heat treatment does not need to be performed on the prepared coatings.