The San Francisco 49ers are a professional American football team. The team plays its home games in , while the club's headquarters and practice facility are located in Santa Clara, California. The 49ers are currently members of the Western Division of the National Football Conference (NFC) in the National Football League (NFL).

The 49ers began play in 1946 as a charter member of the All-America Football Conference (AAFC) and joined the NFL in 1950 after the AAFC merged into the older league. The team currently shares the record for most Super Bowl victories (five) with the Pittsburgh Steelers and the Dallas Cowboys, and is the only team with two or more appearances in the Super Bowl that is undefeated in the NFL title game, with a record of 5-0. The 49ers teams of the 1980s and early 1990s are considered by many fans to be among the greatest teams in NFL history.

Three-time Super Bowl MVP Joe Montana, perennial Pro Bowler Ronnie Lott, all-time highest career quarterback rating holder Steve Young, and career-touchdown leader Jerry Rice played for the 49ers during this period. Additionally, some of the most memorable plays (including "The Catch") and games (such as Super Bowl XXIII) were played by this team.