Fray Bentos (Spanish pronunciation: [fɾaj ˈβentos]) is the capital city of the Río Negro Department, in south-western Uruguay, at the Argentina-Uruguay border, near the Argentine city of Gualeguaychú. Its port on the Uruguay River is one of the nation's most important harbours. The city hosts the first campus of the Technological University, beside the historically relevant industrial complex Anglo, a World Heritage Site, however, the Port is mainly famous for giving the name to the world renowned Fray Bentos pies.

One of the biggest pulp mills in the world is situated close to Fray Bentos and the Libertador General San Martín Bridge; it was the center of the largest political dispute between Uruguay and Argentina during the 21st century.

The city is close to the border with Argentina and about 160 kilometres (99 mi) due north of Buenos Aires, and 309 kilometres (192 mi) north-west from Montevideo, Uruguay's capital.

The town was founded as 'Villa Independencia' by Decree of 16 April 1859. It became capital of the Department of Río Negro on 7 July 1860 by the Act of Ley Nº 1.475 and its status was elevated to "Ciudad" (city) on 16 July 1900 by the Act of Ley Nº 2.656. Its current name, meaning "Friar Benedict", is derived from a reclusive priest.

Historically, Fray Bentos' main industry has been meat processing. An industrial plant owned by the Societe de Fray Bentos Giebert & Cie., the Liebig Extract of Meat Company (LEMCO), was founded there in 1863. It was closed in 1979, after 117 years in operation. A local history museum opened on the site in March 2005.

The surroundings of Fray Bentos were the location of the crash of Austral Flight 2553, in which 74 people were killed (69 passengers and 5 crew) on 10 October 1997.

On 5 July 2015, the city's Barrio Anglo, the location of the industrial plant, was declared a World Heritage Site as the "Fray Bentos Cultural-Industrial Landscape".

In 2023 Fray Bentos had a population of 26,967.