游泳亚目（学名：Natantia）是十足目之下一个已废弃的分类，包括有各个主要以游泳为移动方式的各个科，例如：虾（包括真虾下目及Procarididea）、明虾（枝鳃亚目）及猬虾下目。其他在十足目而不在游泳亚目的物种，都被归入爬行亚目（Reptantia），包括有螃蟹、龙虾、螯虾及其他主要是在海底爬行的较大型物种。这种分类于1963年由马丁·布尔肯罗德（Martin Burkenroad）提倡废除 。他根据原来的爬行亚目物种的特性，发现除了明虾以外，其他十足目的雌性生物在孵化受精后的蛋时，都会把蛋在孵出前沾在雌性的腹足上。根据这特征，他把所有明虾以外的物种重新归类到抱卵亚目去。事实上，现时我们知道游泳亚目是一个并系群，布尔肯罗德把十足目重新分类方法，得到了分子系统发生学的确认。

Natantia (Boas, 1880) is an obsolete taxon of decapod crustaceans, comprising those families that move predominantly by swimming – the shrimp (comprising Caridea and Procarididea), prawns (Dendrobranchiata) and boxer shrimp. The remaining Decapoda were placed in the Reptantia, and consisted of crabs, lobsters and other large animals that move chiefly by walking along the bottom. The division between Natantia and Reptantia was replaced in 1963, when Martin Burkenroad erected the suborder Pleocyemata for those animals that brood their eggs on the pleopods, leaving Dendrobranchiata for the prawns. Under this system, Natantia is a paraphyletic group. Burkenroad's primary division of Decapoda into Dendrobranchiata and Pleocyemata has since been corroborated by molecular analyses.