The Roman Catholic Diocese of Basankusu (Latin: Basankusuen(sis)) is a Latin suffragan diocese in the ecclesiastical province of the Metropolitan Mbandaka-Bikoro in the Democratic Republic of the Congo.

Its cathedral episcopal see is Cathédrale Saints-Pierre-et-Paul (Saints Peter and Paul) in the town of Basankusu.

• Established on 28 July 1926, as Apostolic Prefecture of Basankusu on territory split off from the then Apostolic Vicariate of Nouvelle-Anvers
• 8 January 1948: Promoted as Apostolic Vicariate of Basankusu
• Lost territory on 14 June 1951 to establish the then Apostolic Prefecture of Isangi (now a diocese)
• Promoted on 10 November 1959, as Diocese of Basankusu, ceasing to be exempt

(all Latin Rite, mostly -initially missionary- members of Latin congregations)

Apostolic Prefects of Basankusu

• Gerardo Wantenaar, Mill Hill Missionaries (M.H.M.) (2 February 1927 – 8 January 1948 see below)

Apostolic Vicars of Basankusu

• Gerardo Wantenaar, M.H.M., Titular Bishop of Uzalis (8 July 1948 – 3 December 1951) (see above 8 January 1948 – 3 December 1951)
• Willem van Kester, M.H.M., Titular Bishop of Legia (19 June 1952 – 10 November 1959 see below)

Bishops of Basankusu

• Willem van Kester, M.H.M. (see above 10 November 1959 – 18 November 1974)
• Ignace Matondo Kwa Nzambi, Scheutists (C.I.C.M.) (18 November 1974 – 27 June 1998), appointed Bishop of Molegbe
• Joseph Mokobe Ndjoku (9 November 2001 - ...), previously Apostolic Administrator (1998 – 9 November 2001) while Bishop of Bokungu–Ikela (Democratic Republic of Congo) (6 December 1993 – 9 November 2001)

• Roman Catholicism in the Democratic Republic of the Congo

• Giga-Catholic Information
• Catholic Hierarchy

1°13′13″N 19°48′10″E / 1.2204°N 19.8029°E / 1.2204; 19.8029