Saint Autonomus (Greek: Άγιος Αυτόνομος; died 313) is a martyr saint. He is said to have been an Italian bishop who escaped the Diocletianic Persecution by migrating to Bithynia in Asia Minor. He evangelized the region, served as first bishop of Claudiopolis and was subsequently martyred.

Saint Autonomus
Old-believers icon of St. Automonus, Ukraine
Bishop and Martyr
Born	unknown Italy
Died	c. 313 Asia Minor
Venerated in	Roman Catholic Church Eastern Orthodox Church
Feast	12 September

"Autonomus" is a frequent misspelling of "autonomous".

In the Eastern Orthodox Church, his feast day is celebrated on September 12.