United Press International (UPI) is an American international news agency whose newswires, photo, news film, and audio services provided news material to thousands of newspapers, magazines, radio and television stations for most of the 20th century until its eventual decline beginning in the early 1980s. At its peak, it had more than 6,000 media subscribers. Since the first of several sales and staff cutbacks in 1982, and the 1999 sale of its broadcast client list to its main U.S. rival, the Associated Press, UPI has concentrated on smaller information-market niches.

Formally named United Press Associations for incorporation and legal purposes but publicly known and identified as United Press or UP, the news agency was created by the 1907 uniting of three smaller news syndicates by the Midwest newspaper publisher E. W. Scripps. It was headed by Hugh Baillie (1890–1966) from 1935 to 1955. At the time of his retirement, UP had 2,900 clients in the United States, and 1,500 abroad.

In 1958, it became United Press International after absorbing the International News Service (INS) in May. As either UP or UPI, the agency was among the largest newswire services in the world, competing domestically for about 90 years with the Associated Press (AP) and internationally with AP, Reuters and Agence France-Presse (AFP).

At its peak, UPI had more than 2,000 full-time employees and 200 news bureaus in 92 countries; it had more than 6,000 media subscribers. With the rising popularity of television news, the business of UPI began to decline as the circulation of afternoon newspapers, its chief client category, began to fall. Its decline accelerated after the 1982 sale of UPI by the Scripps company.

The E.W. Scripps Company controlled United Press until its absorption of William Randolph Hearst's smaller competing agency, INS, in 1958 to form UPI. With the Hearst Corporation as a minority partner, UPI continued under Scripps management until 1982.

Since its sale in 1982, UPI has changed ownership several times and was twice in Chapter 11 bankruptcy reorganization. With each change in ownership came deeper service and staff cutbacks and changes of focus and a corresponding shrinkage of its traditional media customer base. Since the 1999 sale of its broadcast client list to its one-time major rival, the AP, UPI has concentrated on smaller information market niches. It no longer services media organizations in a major way.

In 2000, UPI was purchased by News World Communications, an international news media company founded in 1976 by Unification Church leader Sun Myung Moon.

It now maintains a news website and photo service and electronically publishes several information product packages. Based mostly on aggregation from other sources on the Web and gathered by a small editorial staff and stringers, UPI's daily content consists of a newsbrief summary service called "NewsTrack," which includes general, business, sports, science, health and entertainment reports, and "Quirks in the News." It also sells a premium service, which has deeper coverage and analysis of emerging threats, the security industry, and energy resources. UPI's content is presented in text, video and photo formats, in English, Spanish, and Arabic.