The Diocese of Jeonju (Latin: Dioecesis Ieoniuensis) is a Latin Church ecclesiastical territory or diocese of the Catholic Church in South Korea. It is in the ecclesiastical province of the metropolitan Archdiocese of Gwangju, yet depends on the missionary Dicastery for Evangelization.

Its cathedra is in the Joongang Cathedral of the Sacred Heart of Jesus, in the episcopal see of Jeonju 전주시, Jeollabuk-do 전라북도. It also has a former cathedral, now Jeondong Church of the Sacred Heart of Jesus, in Jeonju. Both are named for the Sacred Heart of Jesus.^[1]

• Established on 13 April 1937 by Pope Pius XI as the Apostolic Prefecture of Zenshu, on territory split off from the then Apostolic Vicariate of Taiku
• Renamed on 12 July 1950 by Pope Pius XII as Apostolic Prefecture of Jeonju 전주 / Chŏnju / 全州 (正體中文) / Ieoniuen(sis) (Latin)
• Promoted on 21 January 1957 as Apostolic Vicariate of Jeonju 전주 / Chŏnju / 全州 (正體中文) / Ieoniuen(sis) (Latin), hence entitled to a titular bishop.
• Promoted again by Pope John XXIII on 10 March 1962 as Diocese of Jeonju 전주 / Chŏnju / 全州 (正體中文) / Ieoniuen(sis) (Latin) ^[1]

As of 2014^[update], it pastorally served 190,465 Catholics (10.2% of 1,872,965 total) on 8,066 km² in 93 parishes and 5 missions with 213 priests (209 diocesan, 4 religious), 341 lay religious (7 brothers, 334 sisters) and 42 seminarians.^[1]

• List of Catholic Dioceses in Korea