Disclosed herein are oral preparations and their production process. The oral preparations are each composed of a complex and a coating composition applied on the complex. The complex has been obtained by dispersing or dissolving a drug having an unpleasant taste and a gastric high-molecular compound in a low melting-point substance heated to and molten at its melting point or higher and granulating the resulting mixture. The coating composition is composed of an insoluble high-molecular compound and a disintegrator at a weight ratio of from 80:20 to 99:1. In the form of microparticles or the like that contain the drug having the unpleasant taste, each oral preparation according to the present invention can maintain the masking of the unpleasant taste of the drug and the release profile of the drug even under acidic conditions.