Regina Mundi Cathedral, Catholic cathedral in Bujumbura, Burundi.

Regina Mundi Cathedral is a Catholic church built in the late 1950s on a basilican plan: a central nave about 20 m wide flanked by two aisles, an apse choir ringed by an ambulatory, and no transept. Its central roof ridge reaches about 20 m, a roughly 40 m campanile stands at its left, and the facades are painted vanilla yellow. Belgian painter Maurice Hizette made the stained glass, including the central window of the Virgin and Child.

Built in the late 1950s and in use from 1958, the church became a cathedral only in 1959, when Michel Ntuyahaga was named Bujumbura's first native bishop. Its foundation stone was laid on 15 August 1956 by Jean-Paul Harroy, then vice-governor-general of Ruanda-Urundi, and it was consecrated on 8 January 1962 by Mgr Mojaisky-Perelli. The Archdiocese of Bujumbura was created on 25 November 2006 by Pope Benedict XVI.

The name Regina Mundi means Queen of the World, the title of the Virgin Mary holding the Child Jesus shown in the central stained-glass window above the entrance. The windows are by the Belgian painter Maurice Hizette. On 18 December 1961 Ruanda-Urundi issued six stamps, with a surcharge, to fund the building's completion; two show the facade, two an angled view and two the front windows, and they name the city Usumbura.

Access is via a staircase leading to a terrace spanning the full width of the facade, then through three carved wooden lattice doors under a porch. The campanile, about 40 m high, gives a wide view over the city and Lake Tanganyika. A large wooded garden extends behind and along the left side. The building has no organ.

On 18 December 1961 Ruanda-Urundi issued a set of six surcharged stamps to fund the cathedral's completion: two show the facade head-on, two an angled view, and two the stained glass of the main front. The stamps name the city Usumbura, Bujumbura's former name.