Serie B Basket is the third-tier men's basketball league in Italy.
Serie B Basket first began in the 1937–38 season as the second level of the Italian basketball league system, and it remained the 2nd-tier level of the Italian basketball pyramid until the 1954–55 season. Serie B Basket was downgraded to being the third-tier level on the Italian basketball pyramid from the 1955–56 season, until the 1964–65 season. From the 1965–66 season, through the 1973–74 season, it was once again the second-tier level on the Italian basketball pyramid, being one tier below the Serie A Basket.
Serie B Basket was then once again downgraded to being the third-tier level league on the Italian basketball pyramid from the 1974–75 season, through the 1985–86 season. With the creation of the Serie B Excellence (Italian: Serie B d'Eccellenza), Serie B2 was downgraded to being the fourth-tier level on the Italian basketball pyramid, and was renamed to Serie B2 Basket.
From 2008 to 2011, the league was known as Serie B Amateurs Basket (Italian: Serie B Dilettanti Basket). From 2011 to 2014, the league was known as the National B Division Basket (Italian: Divisione Nazionale B Basket). Since 2014, the league has once again been known as the Serie B Basket, and has once again been the third-tier level on the Italian basketball pyramid.