Big Brother 8 is the eighth season of the American reality television series Big Brother. It is based upon the Netherlands series of the same name, which gained notoriety in 1999 and 2000. The series premiered on CBS on July 5, 2007 and lasted eleven weeks until the live finale on September 18, 2007. The eighth season saw little to no change in ratings. The season premiered to 7.40 million viewers, the lowest premiere numbers for any season at the time. The season finale had 8.51 million viewers, making it the second lowest rated finale at the time. In total, the series averaged 7.52 million viewers, only 0.4 behind the previous edition. Big Brother 8 featured 14 HouseGuests, the same amount that was featured in the previous season. The series ended after 81 days, in which HouseGuest Dick Donato was crowned the winner, and his daughter Daniele Donato the runner-up.

Big Brother is an American television reality competition show based on the Dutch reality show of the same name created by producer John de Mol Jr. in 1997. The series takes its name from the character in George Orwell's 1949 novel Nineteen Eighty-Four. The American series launched on July 5, 2000 on CBS, and since the discontinuation of the Spanish version in 2022, is the longest-running adaptation in the Big Brother franchise.