The Lutjanidae or snappers are a family of perciform fishes, mainly marine but with some members living in estuaries, and entering fresh water to feed. Some are important food fish. One of the best known is the red snapper.

Snappers are found in the tropical and subtropical regions of all the oceans. They can grow to about a metre in length. Most feed on crustaceans or other fish, though a few are plankton-feeders. They can be kept in aquaria, but mostly grow too fast to be popular aquarium fish. They live at depths of up to 450m.

About 100 species of snapper are currently recognised, divided into about 16 genera. A very large number of fish species have "snapper" in their common name; most but not all of these are members of the family Lutjanidae. Almost all the 60 or so species in the genus Lutjanus have common names including the word "snapper".

In New Zealand waters, there are two fishes commonly known as Snapper, neither of them members of the family Lutjanidae. Because of a misidentification, they were originally thought to be the same species. One is the Gilthead Seabream, Sparus aurata, the other the Squirefish Chrysophrys auratus. Both are members of the family Sparidae of porgies and sea breams. The Squirefish was named "snapper" named by Captain James Cook, and placed in the wrasse genus Labrus by J. R. Forster in work published in 1801. The name snapper (also Cockney Snapper, Golden Snapper, Old Man Snapper, or Pink Snapper) is also used for it in Australia. The Gilthead Seabream has, for many centuries, been called Tamure by the indigenous Maori.