The Liga Sudamericana de Baloncesto (LSB), or FIBA Liga Sudamericana de Baloncesto (Portuguese: Liga Sul-Americana de Basquete, English: South American Basketball League), also commonly known as FIBA South American League, is the second-tier level South American professional basketball competition at the club level, with the first-tier level now considered the panamerican competition of the Champions League.

The competition is organized by the South American Basketball Association (ABASU), which operates as a regional sub-zone of FIBA Americas.

The winner of each year's competition gets a place at the upcoming edition of the Basketball Champions League Americas.

Atenas in 1997 and Vasco da Gama in 1999 were the only two teams that represented South America in the competition which also included NBA champions.

On 24 September 2019, FIBA launched the competition, which derives its name and branding from the European Basketball Champions League.