The Campeonato Brasileiro Série B (commonly referred to as the Brasileirão Série B, the Série B or the Brazilian Série B to distinguish it from the Italian Serie B), and currently officially called Brasileirão Série B Superbet for sponsorship reasons) is the second tier of the Brazilian football league system, which is organized by the Brazilian Football Confederation.

The competition was played for the first time in 1971, and for a long time, the competition format was inconsistent, with changes happening frequently in the past. Also, there were years where the competition wasn't played at all.

Since 2006 it has been contested by 20 teams in a double round-robin format with 38 matches, with the top four teams being promoted to the Campeonato Brasileiro Série A group and the bottom four teams being relegated to the Campeonato Brasileiro Série C.

Brazil Serie B is the second tier of professional football in Brazil, featuring a highly competitive league that showcases emerging talent and established clubs vying for promotion to the top-flight Campeonato Brasileiro Série A. Established in 1971, the tournament operates annually, typically running from April to November, and includes 20 teams competing in a round-robin format. Teams play each other twice, both home and away, with points awarded for wins and draws. At the end of the season, the top four teams earn promotion to Série A, while the bottom four are relegated to Série C. Known for its passionate fan base, intense matches, and a mix of seasoned veterans and promising young players, Brazil Serie B serves as a vital platform for clubs aiming to reach the highest level of Brazilian football.