The 2017–18 San Antonio Spurs season was the 51st season for the franchise, the team's 42nd season in the National Basketball Association (NBA), and its 45th in the San Antonio area. The Spurs finished the season with a 47–35 record and the seventh seed in the Western Conference. In the first round of the playoffs, the team was defeated in five games by the defending champion and eventual NBA champion Golden State Warriors, the team that swept them in last season's Western Conference finals. The 2017–18 season was the final season that Tony Parker and Manu Ginóbili played for the team, and Kawhi Leonard and Danny Green would be traded following the season to the Toronto Raptors.
Star forward Kawhi Leonard played a career-low nine games during the season due to a quadriceps injury. On March 10, 2018, the Spurs finished with a losing season on the road for the first time since 1997 after a loss to the Oklahoma City Thunder. However, the team finished the season with a winning record, doing so for an NBA-record 21st consecutive season. With a loss to the Los Angeles Clippers on April 3, 2018, the Spurs' streak of 18 straight seasons of 50 wins or more (and 20 straight seasons with a winning percentage of .600 or better) ended; it had lasted since the 1997–98 season. The Spurs clinched a playoff spot on April 9, 2018 with a win over the Sacramento Kings in their last home game of the season. They finished the regular season with a 47–35 record and held the seventh seed in the Western Conference.
In the first round of the playoffs, the Spurs faced the second-seeded Golden State Warriors and lost in five games.
After the end of the 2017-18 season, Leonard asked to be traded. On July 18, 2018, Leonard and Danny Green were traded to the Toronto Raptors, for DeMar DeRozan, Jakob Pöltl, and a first-round draft pick.
This season was the last season that franchise mainstays Tony Parker and Manu Ginóbili played for the Spurs. After 17 years with the team, Parker signed a two-year deal with the Charlotte Hornets and retired after one season. On August 27, 2018, Ginobili announced his retirement after 16 seasons, all with the Spurs. Ginobili was the second-oldest active player in the league at the time of his retirement, behind only the Atlanta Hawks' Vince Carter. This marked the official end of the Spurs' "Big Three" era; the trio of Parker, Ginobili, and Tim Duncan won a total of four NBA championships together during their years with the team.