The invention discloses a composition capable of preventing leaf surfaces of plants from salt mist injury and belongs to the technical field of plant protection. The invention relates to the composition capable of preventing leaf surfaces of plants from salt mist injury. The composition is prepared from 0.5-10 parts of a water soluble high molecule, 0-10 parts of waterborne polyurethane resin, 0.5-10 parts of glycerinum, 0.01-5 parts of water soluble cellulose, 0.01-5 parts of alginate, 0-5 parts of a surfactant and 0-5 parts of a preservative, wherein the water soluble high molecule is selected from at least one of polyvinyl alcohol, polyoxyethylene and polyethylene glycol. The composition forms protecting films on the surfaces of the leaf surface of the plants to prevent salt mist from being in direct contact with the leaf surfaces of the plants and effectively prevent bad results of black and yellow, even withered leaf surfaces as salt marsh is left on the leaf surfaces of the plants so that the damage to growth of the plants by the salt mist is alleviated greatly, and a very good protecting role is played.