A powerful center at 6'7", Unseld played for the University of Louisville, located in his hometown. During his varsity career with the Cardinals, he averaged 20 points and 19 rebounds a game. He was named All-American at Louisville his senior year. He led the Conference in rebounding for 3 straight years. Unseld was the second overall pick in the 1968 NBA draft by the Baltimore Bullets, where he earned Rookie of the Year and MVP honors in the same season. He is one of two NBA players to have accomplished that feat. He went on to become NBA Finals MVP in 1978.

Unseld now operates a private school in Baltimore, Maryland, which was started in 1982 by the Unseld family.