The Cambaridae are the largest of the four families of freshwater crayfish, with over 400 species.

[1] Most of the species in the family are native to the United States east of the Great Divide and Mexico, but fewer range north to Canada, and south to Guatemala and Honduras.

The species in the genus Cambaroides are only found outside North America, as they are restricted to eastern Asia.

[2] A few species, including the invasive Procambarus clarkii and Faxonius rusticus, have been introduced to regions far outside their native range (both in North America and other continents).

[3] The oldest fossils of the family are known from the Late Jurassic Morrison Formation of western North America.