二趾树懒（学名：Choloepus didactylus）是披毛目树懒亚目二趾树懒科下的一种，与霍氏树懒构成整个二趾树懒属及二趾树懒科。生活于南美洲，包括委内瑞拉、圭亚那、巴西北部至亚马逊河。

二趾树懒是独行侠，夜行性及草食性动物，主要栖息于雨林内。能够游泳，因此可跨越河流及小溪。除了人类会威胁其存活外，大型猛禽也大可不费吹灰之力将其捕捉，如如冕雕及角雕，猫科的虎猫也会袭击牠们。

Linnaeus's two-toed sloth (Choloepus didactylus), also known as the southern two-toed sloth, unau, or Linne's two-toed sloth is a species of sloth from South America, found in Venezuela, the Guyanas, Colombia, Ecuador, Peru, and Brazil north of the Amazon River. There is now evidence suggesting the species's range expands into Bolivia.