The Micronesians or Micronesian peoples are various closely related ethnic groups native to Micronesia, a region of Oceania in the Pacific Ocean. They are a part of the Austronesian ethnolinguistic group, which has an Urheimat in Taiwan.

Ethno-linguistic groups classified as Micronesian include the Carolinians (Northern Mariana Islands), Chamorros (Guam & Northern Mariana Islands), Chuukese, Mortlockese, Namonuito, Paafang, Puluwat and Pollapese (Chuuk), I-Kiribati (Kiribati), Kosraeans (Kosrae), Marshallese (Marshall Islands), Nauruans (Nauru), Palauan, Sonsorolese, and Hatohobei (Palau), Pohnpeians, Pingelapese, Ngatikese, Mwokilese (Pohnpei), and Yapese, Ulithian, Woleian, Satawalese (Yap).

Based on the current scientific consensus, the Micronesians are considered, by linguistic, archaeological, and human genetic evidence, to be a subset of the sea-migrating Austronesian people, who include the Polynesians and the Melanesians. Austronesians were the first people to invent oceangoing sailing technologies (notably double-hulled sailing canoes, outrigger boats, lashed-lug boat building, and the crab claw sail), which enabled their rapid dispersal into the islands of the Indo-Pacific. From 2000 BCE the Austronesians assimilated (or were assimilated by) the earlier populations on the islands in their migration pathway. This intermingling occurred in the northern coast of New Guinea and adjacent islands, which was the location where the Oceanic language family developed around four thousand years or so ago, after the Austronesian languages of this area grew distinct and became a separate branch of the Austronesian family.

Migrants entered Micronesia from the east and the west. Migrants from the west came from the Philippines and Indonesia, and settled the Marianas around 3500 years ago, after which Palau was settled around 3000 years ago. Migrants from the east came from eastern Melanesia and settled the Gilbert Islands, Marshall Islands, eastern and central Caroline Islands, Sonsorol, Pulo Anna, Merir and Tobi. The migrants from the east belonged to the Lapita culture and settled eastern Micronesia over the course of several hundreds of years from perhaps the Santa Cruz Islands, around 500-100 BC. In the following centuries, the Oceanic language variant brought by the Lapita migrants diverged and became the Micronesian branch of the Oceanic languages. John Lynch tentatively proposes a relationship between the Micronesian languages and the Loyalty Islands languages of Melanesia, but with the caveat "that this is something that could well be further investigated, even if only to confirm that Micronesian languages did not originate in the Loyalties." Yap was settled separately approximately 2000 years ago, as its language was brought by an Oceanic-speaking source in Melanesia, perhaps the Admiralty Islands.

A 2022 genetic study has shown that the various peoples inhabiting Micronesia have diverse genetic origins and originate from distinct streams of migration. Micronesia was settled by three separate streams of First Remote Oceanian lineage, which corresponds to East Asian ancestry and clusters closely to modern day peoples of the Philippines such as the Kankanaey and the Amis and Atayal of Taiwan. The first wave of First Remote Oceanian lineage settled the Mariana Islands around 2800 BCE. A second separate wave settled Palau around 2400 BCE. A third separate wave settled Central Micronesia around 2100 BCE. The peoples of Central Micronesia and Palau have a degree of Papuan ancestry, but this is absent from the peoples of the Mariana Islands. The study also supports the Admiralty Islands as the source of the Central Micronesian peoples and languages.

The Micronesian peoples can be divided into two cultural groups, the high-islanders and the low-islanders. The Palauans, Chamorros, Yapese, Chuukese, Pohnpeians, Kosraeans, Nauruans and Banabans belong to the high-islander group. The inhabitants of the low islands (atolls) are the Marshallese and the Kiribati, whose culture is distinct from the high-islanders. Low-islanders had better navigation and canoe technology, as a means of survival. High-islanders had access to reliable and abundant resources and did not need to travel much outside of their islands. High islands also possessed larger populations.

Archeological evidence has revealed that some of the Bonin Islands were prehistorically inhabited by members of an unknown Micronesian ethnicity.

Raobeia Ken Sigrah claims that Banabans, native to Banaba, are ethnically distinct from other I-Kiribati. The Banabans were assimilated through forced migrations and the heavy impact of the discovery of phosphate in 1900. After 1945, the British authorities relocated most of the population to Rabi Island, Fiji, with subsequent waves of emigration in 1977, and from 1981 to 1983. Some Banabans subsequently returned, following the end of mining in 1979; approximately 300 were living on the island in 2001. The population of Banaba in the 2010 census was 295. There is an estimated 6,000 people of Banaban descent in Fiji and other countries. The Banabans spoke the Banaban language, which has gone extinct due to a shift to the Gilbertese language, introduced by Christian missionaries that translated the Bible into Gilbertese and encouraged the Banabans to read it. Today, only a few words remain of the original Banaban language. Today, the Banabans speak the Banaban dialect of Gilbertese, which includes words from the old Banaban language.