Scirtoidea is a superfamily of beetles. It is traditionally considered to consist of four families: Clambidae, Decliniidae, Eucinetidae and Scirtidae. However, genetic studies have suggested that Clambidae and Eucinetidae belong to a separate superfamily Clamboidea, which also includes Derodontidae. Scirtoidea and Clamboidea are the two earliest diverging lineages of living polyphagans.