Zdenek Koubek (born Zdena "Zdenka" Koubková, 8 December 1913 – 12 June 1986) was a track athlete from Czechoslovakia.
He won two medals at the 1934 Women's World Games and several national titles in the 100–800 m running, long jump and high jump, and set a few world records in running events.
In 1936, he underwent female to male gender reassignment surgery and retired from athletics.