The Diocese of Ostuni (Latin: Dioecesis Ostunensis or Hostuniensis) was a Roman Catholic diocese located in the town of Ostuni in the province of Brindisi in the region of Apulia in southern Italy. The diocese was in existence by the mid-11th century. In 1818, the diocese was suppressed, and its ecclesiastical territory assigned to the Archdiocese of Brindisi.[1] [2] In 1821, the diocese was revived, but the archbishops of Brindisi were made its perpetual administrator. From 1980 to 1986, Brindisi and Ostuni were suffragans of the ecclesiastical province of Lecce. In 1986, the diocese of Ostuni was completely suppressed and united to the archdiocese of Brindisi.
A bishop of Ostuni in 596, named Melatius, is reported by Pius Bonifacius Gams.[3] It has been shown by Francesco Lanzoni, however, that Melatius was a French bishop of "Rotumo", not a bishop of Ostuni.[4]