Disclosed herein is a granule containing physiologically-active substance which comprises at least(A): a physiologically-active substance;(B): a substance which is stable under neutral condition but disintegrates or dissolves at a pH of 3 or less; and(C): at least one substance selected from the group consisting of straight-chain or branched, saturated or unsaturated monocarboxylic acids having at least 14 carbon atoms and salts thereof, animal fats having a melting point of 40.degree. C. or higher, vegetable fats having a melting point of 40.degree. C. or higher and waxes having a melting point of 40.degree. C. or higher, and which granule further has a protective film comprising at least said substances (B) and (C) on the surface thereof. The protective film has a thickness of preferably at most 20% of the granular diameter and is preferably at least composed of at least 10% by weight of the substance (B) and at most 90% by weight of the substance (C). Granules having this specific protective film on the surface thereof have the use as a feed additive composition. A method for preparing said granules is also disclosed.