重足下目（学名：Gravigrada）是哺乳类真兽下纲的一个弃用生物分类名称，跟反刍下目和厚皮下目合组成为「第四类」Quaternates。这个分类由法国自然学家Henri-Marie Ducrotay de Blainville于1839创建，包括以下三个属：象属（Elephas）、恐象属（Dinotherium）及海牛属（Manatus，即现在的Trichechus）。这个分类之下的物种现时已划归海牛目（Sirenia）和长鼻目（Proboscidea），均属于非洲兽总目。

Gravigrada is the name of a suborder of Mammals established by the French naturalist Henri-Marie Ducrotay de Blainville in 1839, within the order Quaternates. He included three genera in the suborder: Elephas, Dinotherium and Manatus (Trichechus).

The name is no longer considered valid, as the animals that were included within Gravigrada are now believed to belong to two different orders, Sirenia and Proboscidea.