The painted frogfish was first formally described as Lophius pictus in 1794 by the English biologist George Shaw with its type locality given as Tahiti in the Society Islands.

[4] The 5th edition of Fishes of the World classifies the genus Antennarius in the family Antennariidae within the suborder Antennarioidei within the order Lophiiformes, the anglerfishes.

[5] The painted frogfish has the genus name Antennarius which suffixes -ius to antenna, an allusion to first dorsal spine being adapted into a tentacle on the snout used as a lure to attract prey.

The specific name pictus means "painted", the body being described by Shaw as being brown marked with red-margined yellowish blotches.

[2] Like other members of its family, it has a globulous, extensible body, with soft skin is covered with small dermal spinules.

The second dorsal spine is practically straight and is mobile, and the third one is bent towards the back of the body; both are membranously attached to the head.