The invention relates to water-soluble tilmicosin phosphate as well as a preparation method and application thereof. The preparation method comprises the steps of adding a substance containing a phosphate radical into water for dissolving, heating to 50-70 DEG C, adding tilmicosin for dissolving, adjusting the pH value to 5.0-8.0 by virtue of an alkaline substance, maintaining the temperature for 15-30 minutes, adding a solid adsorbent, stirring, filtering, concentrating, and drying, so as to obtain water-soluble tilmicosin phosphate. Prepared water-soluble tilmicosin phosphate is used for preventing and treating respiratory tract infection of animal stud stocks and pets. Compared with the prior art, the preparation method has the advantages that water is taken as a solvent, so that the environmental pollution caused due to use of organic solvents such as DMF, toluene and dichloromethane is avoided; and a preparation prepared from water-soluble tilmicosin phosphate has good palatability, so that the ingestion of animals is not influenced; and water-soluble tilmicosin phosphate is applied to the prevention and control of animal diseases and has good mass uniformity and stability and very good application prospects.