The Percophidae, duckbills, are a family of percomorph fishes, from the order Trachiniformes, found in tropical and subtropical waters of the Atlantic and Indian Oceans and in the southwestern and southeastern Pacific.

Percophidae was first proposed as a family in 1839 by the English zoologist William Swainson as a subfamily of the Percidae.

[2] The 5th edition of Fishes of the World classifies this family within the order Trachiniformes and divides it into the subfamilies Bempropinae, Henerocoetinae and Percophinae.

[3] Other authorities recognise thie family Percophinidae as being monotypic with only Percophis classified within it and placed in the suborder Percophoidei of the order Perciformes.

[4] The family Percophidae is divided into three subfamilies[3] The species in the family Percophidae are elongated, benthic fishes with an anteriorly depressed head, a broad flat snout which gives rise to the common name duckbills.