The Roman Catholic Diocese of Mbujimayi (Latin: Mbugimayen(sis)) is a Latin diocese in the Democratic Republic of the Congo's Kasai Oriental province. It is a suffragan in the ecclesiastical province of Kananga.

Its cathedral episcopal see is the Cathédrale Saint-Jean-Baptiste de Bonzola in the city of Mbuji-Mayi.

• Established on 22 November 1963 as Apostolic Administration of Mbuji-Mayi, on territories split off from the Metropolitan Archdiocese of Luluabourg and the Diocese of Kabinda
• 3 May 1966: Promoted as Diocese of Mbujimayi

(all Latin Rite)

Apostolic administrator

• Joseph Ngogi Nkongolo (1963 - 3 May 1966 see below), previously Titular Bishop of Lebedus & Apostolic Vicar of Luebo (Congo-Kinshasa) (25 April 1959 – 10 November 1959), promoted first Bishop of Luebo (Congo-Kinshasa) (10 November 1959 – 3 May 1966)

Suffragan Bishops of Mbujimayi

• Joseph Ngogi Nkongolo (see above 3 May 1966 – 26 November 1991)
• Tharcisse Tshibangu Tshishiku (26 November 1991 – 1 August 2009), previously Titular Bishop of Scampa & Auxiliary Bishop of Kinshasa (Congo-Kinshasa) (1 September 1970 – 26 November 1991)
• Bernard Emmanuel Kasanda Mulenga (1 August 2009 – ...), previously Titular Bishop of Utimmira (14 February 1998 – 1 August 2009) and Auxiliary Bishop of Mbujimayi (14 February 1998 – 1 August 2009)

• Bernard Emmanuel Kasanda Mulenga (1999–2009), appointed Bishop here

• Roman Catholicism in the Democratic Republic of the Congo

• GCatholic.org, with incumbent biography links
• Catholic Hierarchy