Grêmio Foot-Ball Porto Alegrense (Portuguese pronunciation: [ˈɡɾemju futʃiˈbɔw ˌpoɾtw ɐleˈɡɾẽsi]), commonly known as Grêmio, is a Brazilian professional football club based in Porto Alegre, capital city of the Brazilian state of Rio Grande do Sul. The club plays in the Campeonato Brasileiro Série A, the first division of the Brazilian football league system, and the Campeonato Gaúcho, Rio Grande do Sul's top state league. The club was founded in 1903 by European immigrants Englishman Andy Fairbank and German Paul Cochlin, although Grêmio's official website cites Cândido Dias da Silva and other 32 unnamed men as founders. Grêmio's home stadium is the Arena do Grêmio, which the team moved to in 2013. Prior to that, Grêmio played at Estádio Olímpico Monumental since 1954.

In 1983, Grêmio became champions of the Intercontinental Cup after defeating Hamburger SV 2-1. Additionally, Grêmio is tied with São Paulo, Santos, Palmeiras, and Flamengo for the most Copa CONMEBOL Libertadores de América titles, having won a total of three each.

As of 2017, Grêmio was ranked number one in the CBF club rankings and is listed by Forbes as the third most valuable football club in the Americas with an estimated value of $295.5 million. Grêmio has won 41 Campeonato Gaúcho, 2 Campeonato Brasileiro Série A, 1 Campeonato Brasileiro Série B, 1 Supercopa do Brasil, 1 Copa Sul and 5 Copa do Brasil. Internationally, Grêmio has won 1 Intercontinental Cup, 3 Copa Libertadores de América, 2 Recopa Sudamericana and 1 Sanwa Bank Cup. Grêmio usually plays in a tricolor (blue, black and white) striped shirt, black shorts and white socks, which originated the team's nickname.

Grêmio has a long-standing and intense rivalry with Internacional, which is widely regarded as one of the fiercest in Brazil and around the world. Matches between the two teams are known as Grenal and are highly anticipated events.