类人猿下目（学名Simiiformes）是一类高等灵长类，由旧世界猴及猿组成。牠们比原猴亚目的要大。

类人猿下目分成三类。阔鼻小目于约4000万年前分支出来，只余下狭鼻小目留在旧世界。狭鼻小目再于2500万年前分支开成旧世界猴及猿。猴是一个并系群。早期分类将灵长目分为原猴亚目及类人猿亚目。

以下是类人猿下目的分类：

The simians (infraorder Simiiformes, Anthropoidea) are the higher primates: the Old World monkeys and apes, including humans (together being the catarrhines), and the New World monkeys or platyrrhines.

The simian line and the tarsier line diverged about 60 million years ago. Forty million years ago, simians from Africa colonized South America, giving rise to the New World monkeys. The remaining simians (catarrhines) split 25 million years ago into apes and Old World monkeys.