The present invention provides a novel oral administration preparation that enables administration of silodosin, which is a drug with extremely strong bitterness, without a foreign-body sensation even without water, and has dissolution properties of being able to reproduce an effective blood concentration for the treatment of dysuria associated with benign prostatic hyperplasia or the like.The present invention relates to a masked particle and a novel oral administration preparation comprising the masked particle or the like, wherein the masked particle obtained by granulating or coating a drug particle comprising a fine powder of silodosin with a coating agent comprising a non-enteric polymer, and a content of the non-enteric polymer is 80 parts by mass to 400 parts by mass relative to 100 parts by mass of silodosin.