The Guti (/ˈɡuːti/), also known by the derived exonyms Gutians or Guteans, were a people of the ancient Near East who both appeared and disappeared during the Bronze Age. Their homeland was known as Gutium (Sumerian: 𒄖𒌅𒌝𒆠, Gutūm^KI or 𒄖𒋾𒌝𒆠, Gutium^KI). Conflict between people from Gutium and the Akkadian Empire has been linked to the collapse of the empire, towards the end of the 3rd millennium BCE. Although economic factors, climate change and internal strife also played a part. The Guti subsequently overran southern Mesopotamia and formed the short-lived Gutian dynasty of Sumer, overseeing a period of economic decline. The Sumerian king list suggests that the Guti ruled over Sumer for several generations following the fall of the Akkadian Empire.

By the mid 2nd millennium BCE, use of the name "Gutium", by the Assyrians and Babylonians of Mesopotamia, was extended to include all foreigners from northwestern Iran, between the Zagros Mountains and the Tigris River. Various tribes and places to the east and northeast, regardless of ethnicity, were often referred to as Gutians or Gutium, and the name no longer referred to one specific people . For example, Assyrian royal annals use the term Gutians in relation to populations known to have been Medes or Mannaeans. As late as the reign of Cyrus the Great of Persia, the famous general Gubaru (Gobryas) was described as the "governor of Gutium".

Little is known of the origins, material culture or language of the Guti, as contemporary sources provide few details and no artifacts have been positively identified. As the Gutian language lacks a text corpus, apart from some proper names, its similarities to other languages are impossible to verify. The names of Gutian kings suggest that the language was not closely related to any languages of the region at the time, including Sumerian, Akkadian, Hurrian, Hittite, Eblaite and Elamite. Scholars reject the attempt to link Gutian king names to Indo-European languages, which had not yet arrived in the region.

The Guti appear in texts from c. 17th century BC purported copies of inscriptions proposed to be of Lugal-Anne-Mundu (fl. c. 25th century BC – c. 25th century BCE) of Adab as among the nations providing his empire tribute. These inscriptions locate them between Subartu and Assyria in the north, and Marhashi and Elam in the south. This fragmentary text has been described as a "pseudoautobiographical literary composition".

According to the later literary composition Great Revolt against Naram-Sin, Naram-Sin of Akkad's army of 360,000 soldiers defeated the Gutian king Gula'an, despite having 90,000 slain by the Gutians.

The much later Sumerian literary composition Cuthean Legend of Naram-Sin claims Gutium among the lands raided by Annubanini of Lulubum during the reign of Naram-Sin (c.  2254–2218 BCE). Contemporary year-names for Shar-kali-sharri of Akkad indicate that in one unknown year of his reign, Shar-kali-sharri captured Sharlag king of Gutium, while in another year, "the yoke was imposed on Gutium".

During the Akkadian Empire period, the Gutians slowly grew in strength and then established a capital at the Early Dynastic city of Adab. The Gutians eventually overran Akkad, and as the King List tells us, their army also subdued Uruk for hegemony of Sumer, in about 2147~2050 BCE. However, it seems that autonomous rulers soon arose again in a number of city-states, notably Gudea of Lagash.

The Gutians seem also to have briefly overrun Elam at around the same time, towards the close of Kutik-Inshushinak's reign (c.  2100 BCE). On a statue of the Gutian king Erridupizir at Nippur, an inscription imitates his Akkadian predecessors, styling him "King of Gutium, King of the Four Quarters".