The Diocese of Manzini (Latin: Manzinien(sis)) is a Latin Church ecclesiastical territory or diocese of the Catholic Church in Eswatini. It is a suffragan diocese in the ecclesiastical province of the metropolitan Johannesburg in South Africa. Its episcopal see is located in the city of Manzini.

• April 19, 1923: Established as Apostolic Prefecture of Swaziland from the Apostolic Vicariate of Natal in South Africa
• March 15, 1939: Promoted as Apostolic Vicariate of Swaziland
• January 11, 1951: Promoted as Diocese of Bremersdorp
• November 7, 1961: Renamed as Diocese of Manzini

• Fr. Pellegrino Bellezze, OSM (15 March 1923 – 1932)
• Fr. Romualdo Migliorini, OSM (8 July 1933 – 1939)

• Costantino Maria Attilio Barneschi, OSM (15 March 1939 – 11 January 1951 see below)

• Costantino Maria Attilio Barneschi, OSM (see above 11 January 1951 – 7 November 1961 see below)

• Costantino Maria Attilio Barneschi, OSM (see above 7 November 1961 – 21 May 1965)
• Girolamo Maria Casalini, OSM (18 December 1965 – 24 January 1976)
• Aloysius Isaac Mandlenkhosi Zwane (24 January 1976 – 10 August 1980)
• Louis Ncamiso Ndlovu, OSM (1 July 1985 – 27 August 2012)
• José Luís Ponce de León, IMC (29 November 2013 – present)

• Catholic Church in South Africa
• Catholic Church in Eswatini

• GCatholic.org
• Catholic Hierarchy

26°29′S 31°22′E / 26.483°S 31.367°E / -26.483; 31.367