原猴在动物分类学上属于灵长目的一个亚目——原猴亚目。主要分布于非洲的马达加斯加以及东亚和南亚。新的分类方法中原猴已不包括跗猴科(Tarsiidae)。

原猴包括：

原猴大多像小型的啮齿动物和食虫动物。尾巴比较长。四肢行走。

Strepsirrhini or Strepsirhini (/ˌstrɛpsəˈraɪniː/; STREP-sə-RY-nee) is a suborder of primates that includes the lemuriform primates, which consist of the lemurs of Madagascar, galagos ("bushbabies") and pottos from Africa, and the lorises from India and southeast Asia. Also belonging to the suborder are the extinct adapiform primates, a diverse and widespread group that thrived during the Eocene (56 to 34 million years ago [mya]) in Europe, North America, and Asia, but disappeared from most of the Northern Hemisphere as the climate cooled. The last of the adapiforms died out at the end of the Miocene (~7 mya). Adapiforms are sometimes referred to as being "lemur-like", although the diversity of both lemurs and adapiforms does not support this comparison. The two leading taxonomic classifications for the suborder divide living strepsirrhine primates into either two superfamilies (Lemuroidea and Lorisoidea) within the infraorder Lemuriformes or two infraorders, Lemuriformes and Lorisiformes. The suborder represents a related group, and replaced the widely used and now obsolete suborder Prosimii ("prosimians"), which included strepsirrhines and tarsiers, a grouping based primarily on shared anatomical traits. Today, Strepsirrhini excludes the tarsiers, which are now grouped in the other major primate suborder, Haplorhini, along with the monkeys and apes (simians or anthropoids). Strepsirrhines are often inappropriately referred to as "living fossils". Instead, they have evolved for millions of years under natural selection, and have diversified to fill many ecological niches. Some of their traits may be derived from ancestral primates, while others are unique to strepsirrhines.