The Yup'ik people (also Central Alaskan Yup'ik, plural Yupiit), are an Eskimo people of western and southwestern Alaska ranging from southern Norton Sound southwards along the coast of the Bering Sea on the Yukon-Kuskokwim Delta (including living on Nelson and Nunivak Islands) and along the northern coast of Bristol Bay as far east as Nushagak Bay and the northern Alaska Peninsula at Naknek River and Egegik Bay.

They are one of the four Yupik peoples of Alaska and Siberia, closely related to the Alutiiq (Pacific Yupik) of southcentral Alaska, the Siberian Yupik of St. Lawrence Island and Russian Far East, and the Naukan of Russian Far East. The Yupiit speak the Central Alaskan Yup'ik language. The people of Nunivak Island, speakers of the Nunivak Island dialect of Central Alaskan Yup'ik, call themselves Cup'ig (plural Cup'it); the people of Hooper Bay and Chevak, speakers of the Hooper Bay-Chevak dialect, call themselves Cup'ik (plural Cup'it).

Yupiit are the most numerous of the various Alaska Native groups and speak the Central Alaskan Yup'ik language, a member of the Eskimo-Aleut family of languages. As of the 2000 U.S. Census, the Yupiit population in the United States numbered over 24,000,, of whom over 22,000 lived in Alaska, the vast majority in the seventy or so communities in the traditional Yup'ik territory of western and southwestern Alaska.