St. John Arena is a multi-purpose arena on the campus of The Ohio State University in Columbus, Ohio, USA. The arena was named for Lynn St. John, who served as Ohio State's men's basketball coach and athletic director until 1947.

Located on north campus between Woody Hayes Drive and Lane Avenue, the 13,276-seat arena was built in 1956. When it housed the Ohio State Buckeyes men's basketball team from its completion until 1998, it saw the Buckeyes win the 1960 National Championship and five straight Big Ten titles from 1960 to 1964 under coach Fred Taylor. The men's and women's basketball teams moved to their current home, Value City Arena at the Jerome Schottenstein Center, in 1998. The arena now houses the school's men's and women's volleyball teams, men's and women's gymnastics teams, and wrestling squad. It also hosts the annual Buckeye Classic women's basketball tournament.

In 2004, St. John Arena hosted its first men's basketball game in six years due to a scheduling conflict at the Schottenstein Center. St. John Arena was again used for men's basketball on March 24, 2008, when the Buckeyes hosted an NIT game against the California Golden Bears. The Buckeyes eventually took the 2008 NIT title.

The most popular event still held at the arena is the Skull Session, the pep rally before football games. Two hours prior to kickoff The Ohio State University Marching Band performs Buckeye favorites, and the players and coaches speak to the crowd. With roots back to 1932, the Skull Session also sometimes features the visiting team's marching band, and even local high school bands. Many Buckeye fans arrive hours early to get a good seat for this classic Ohio State tradition.