The invention discloses a heat clearing and pain alleviating veterinary flunixin meglumine coating agent for animals. The coating agent is prepared from the following raw materials: 80 to 120 g/L of flunixin meglumine, 20 to 40 g/L of polyvinyl alcohol-124, 20 to 40 mL/L of water-soluble azone, 80 to 120 mL/L of N-methylpyrrolidone, and 80 to 120 mL/L of glycerin, and the solvent adopts a Tris-HCL(Tris(hydroxymethyl) aminomethane hydrochloride) buffer solution. The invention further discloses a preparation method of the coating agent. A transdermal agent prepared by the invention has the advantages of good film-forming property, capability of slowly releasing medicines, relieving fever and stopping pain and lasting curative effect, small stress and the like. The formula and the preparation method of the coating agent are unique, the treatment effect is remarkable, a protective film can be formed, the medicines at the inner layer of the film are permeated and absorbed, and the outer layer of the film has a protecting effect, and cannot fall off automatically, so that the coating agent has incomparable advantages in comparison with a pouring agent.