Petun ("Tobacco") were an Iroquoian-speaking people, closely related to the Huron-Wendat, who lived in the region of present-day Collingwood, Ontario, in the early to mid-16th century. The name Petun was applied to these people by the French, and refers to the fact that they were particularly noted for cultivating tobacco or Petún. At the time of European contact, the Petun occupied from eight to ten villages located below the Niagara Escarpment along the southwest margin of Georgian Bay. Their precontact population is uncertain but appears to have numbered several thousand.

The Petun differed little from the Huron, who lived one day's journey to the northeast. It appears from historical accounts and archaeology that the Petun were of relatively recent origin, having been formed in late prehistoric times by a union of groups of Iroquoian-speakers moving west from Wendake and other Iroquoian groups from the areas that are now Toronto or Hamilton. They maintained trading relationships with the Chonnonton and Huron, and with the Algonquian-speaking Odawa and Nipissing. They were destroyed or dispersed along with the Huron by the Haudenosaunee in 1649. The surviving Petun joined with the refugee Huron and made extensive journeys through the midwestern US. They eventually settled in the 1850s in Oklahoma, where descendants of both groups now reside under the name Wyandot, a form of the original Huron name for themselves.

The Petun are historically recorded as consisting of two Bands, the Wolves and the Deer, each comprising one principal village and several lesser villages or hamlets. The villages were palisaded, occupied year-round and contained numerous longhouses. The population subsisted by cultivating corn, beans and squash, as well as by hunting and fishing. The Petun are one of the lesser known Aboriginal groups, partly because they were not numerous, but primarily because they were overshadowed in 17th-century European attention by the larger and politically more important Huron Confederacy.

See also Aboriginal People: Eastern Woodlands and general articles under Aboriginal People.