Sport Lisboa e Benfica (Portuguese pronunciation: [spɔɾ liʒˈboɐ i bɐ̃ȷ̃ˈfikɐ]; Euronext: SLBEN), commonly known as simply Benfica or SLB and occasionally as Benfica Lisbon, is a Portuguese multi-sports club based in Lisbon. Although they successfully compete in a number of different sports, Benfica is mostly known for its association football team. Founded in Lisbon in February 28, 1904, it is one of the "Três Grandes" (Big Three, in English), football clubs in Portugal, with Futebol Clube do Porto and Sporting Clube de Portugal being the other two clubs, Benfica's biggest rivals. Benfica has more than 14 million fans and the Guinness World Record for the football club in the world with most members.^{[citation needed]} Benfica's supporters are often called "Benfiquistas". Benfica was elected by the IFFHS as the 9th most successful European football club of the 20th century and by FIFA as the 12th most successful football club of the 20th century.

It is the most successful Portuguese football club in terms of national titles with 66 titles.