Kenji Shimaoka (嶋岡 健治, Shimaoka Kenji, born May 9, 1949) is a Japanese former volleyball player who competed in the 1968 Summer Olympics, in the 1972 Summer Olympics, and in the 1976 Summer Olympics.
In 1968 he was part of the Japanese team which won the silver medal in the Olympic tournament. He played four matches.
Four years later he won the gold medal with the Japanese team in the 1972 Olympic tournament. He played all seven matches.
At the 1976 Games he was a member of the Japanese team which finished fourth in the Olympic tournament. He played all five matches.