The invention discloses a tilmicosin smell masking preparation and a preparing method thereof, and belongs to the field of antibiotic preparations for livestock. According to the smell masking preparation, tilmicosin and gastric solubility high polymer materials serve as raw materials; and the smell masking preparation is prepared through the steps of fusion through an extruding machine, shearing and conveying. Compared with the prior art, digestion of the tilmicosin smell masking preparation in artificial saliva is slow, so that the effect of stopping releasing of the medicine in the oral cavity is achieved; contact between the medicine and the taste bud of the tongue is less, so that the bitter and hemp tastes can be obviously reduced, and the masking effect is achieved; and the medicine is rapidly released in a 0.01 mol / L hydrochloric acid solution (simulated gastric fluid), and the medicine keeps to play the medicine effect. In addition, the tilmicosin smell masking preparation is prepared with the hot melting extrusion technology, the technology is advanced, the process is simple, organic solvents are not used, and therefore the tilmicosin smell masking preparation is safe and free of pollution; mixing is carried out without a dead corner, the dispersion effect is good, and the medicine losses are fewer; and operation of multiple units is integrated together, so that space is saved, the cost is reduced, and the tilmicosin smell masking preparation is suitable for industrial large-scale production.