The Roman Catholic Diocese of Rio do Sul (Latin: Dioecesis Rivi Australis) is a diocese located in the city of Rio do Sul in the ecclesiastical province of Joinville in Brazil.

• November 23, 1968: Established as Diocese of Rio do Sul from the Metropolitan Archdiocese of Florianópolis and Diocese of Joinville
• November 5, 2024: The diocese became a suffragan see of the newly promoted Archdiocese of Joinville

• Bishops of Rio do Sul (Roman rite), in reverse chronological order
  • Bishop Onécimo Alberton (2014.12.17 - present)
  • Bishop Augustinho Petry (2008.03.19 – 2014.12.17)
  • Bishop José Jovêncio Balestieri, S.D.B. (2000.08.30 – 2008.03.19)
  • Bishop Tito Buss (1969.03.12 – 2000.08.30)

• José Jovêncio Balestieri, S.D.B. (1998-2000)
• Augustinho Petry (2007-2008)

• GCatholic.org
• Catholic Hierarchy