Filefish, one of a group of fish that live in tropical and subtropical seas. One species, the orange filefish, or barnacle eater, ranges as far north as Maine. Most filefishes are less than 12 inches (30 cm) long. They have deep, extremely narrow bodies, and leathery skin covered with tiny prickles. The skin can be used as a substitute for sandpaper. It is uncertain whether the name filefish refers to the skin or to the first back fin, which is a rough, bony spike.

Filefishes belong to the family Balistidae. The orange filefish is Aluterus schoepfi.