Melvin Emmanuel "B. J." Upton (born August 21, 1984, in Norfolk, Virginia) is a Major League Baseball center fielder for the Tampa Bay Rays. Upton is a graduate of Greenbrier Christian Academy.

His nickname, B. J., is short for "Bossman Junior" because his father was once known as Bossman. His brother Justin Upton plays for the Arizona Diamondbacks. B.J. and Justin are the only two brothers in MLB history to be selected in the number one and two slot of the draft (in separate years).

As a member of the 2001 Team USA Junior National team, Upton batted .462 (12-for-26) in nine games. The team went 9–2 and won the Silver Medal in Cuba that year. In 2002, Upton was named a first-team All-American by Baseball America, batting .641 (50-for-78) with 11 doubles, 4 triples, 11 home runs, and 32 RBIs during his senior year at Greenbrier.