Anticoagulation coating and applying method therefor

An anticoagulation coating is formed on the surface of a carrier, and the coating is formed by alternate adsorption of positively charged and negatively charged polyelectrolytes. The present invention has a simple process, can be achieved through a simple solution circulating device, and can obtain a stable coating structure through cross-linking. The preparation method of the present invention is implemented in a mild aqueous environment, has no toxicity of solvents, and is environmental-friendly. After ultrasonic treatment of the polyelectrolyte solution, the solute dispersion of the polyelectrolyte is good, the agglomeration is avoided, and the coating is more even.