Marco Danilo Antonio of Leiningen-Dagsburg (5 April 1808 - 13 March 1874) was the King of Juliana from 1863 until his death. He was a son of Daniel I of Juliana.
Marco married Princess Christine of Libertas in 1826. They had four children:
Christine died in 1868. His son Pietro would succeed him as King of Juliana in 1874.