Leonel Marshall Steward, Sr. (born July 31, 1954) is a Cuban former volleyball player who competed in the 1976 Summer Olympics and in the 1980 Summer Olympics.
In 1976 he was part of the Cuban team which won the bronze medal in the Olympic tournament. He played all six matches.
Four years later he finished seventh with the Cuban team in the 1980 Olympic tournament. He played all six matches again.
His son, also a professional volleyball player and also named Leonel Marshall Jr., is well known for his outstanding vertical jump.