[Problem] To provide compact C crystals of febuxostat, a micronisate of the febuxostat C crystals, and a solid preparation that contains the micronisate, easily disintegrates and is highly stable. [Solution] A solid preparation is produced by crystallizing febuxostat from acetonitrile to obtain compact C crystals of febuxostat, pulverizing the compact C crystals by airflow milling or wet milling, and including the compact C crystals of febuxostat or the micronisate thereof as an active ingredient.