| Jurisdiction: | Diocese |
| Tubarão | |
| Latin: | Dioecesis Tubaraoënsis |
| Local: | Diocese de Blumenau |
| Country: | Brazil |
| Metropolitan: | Florianópolis |
| Rite: | Roman Rite |
| Established: | 28 December 1954 (years ago) |
| Cathedral: | Cathedral of Our Lady of Mercy in Tubarão |
| Area Km2: | 4,531 |
| Population: | 355,435 |
| Population As Of: | 2010 |
| Catholics: | 309,579 |
| Catholics Percent: | 87.1 |
| Bishop: | João Francisco Salm |
| Metro Archbishop: | Wilson Tadeu Jönck, SCI |
| Emeritus Bishops: | Hilário Moser, S.D.B. |
| Map: | File:Diocese de Tubarão.svg |
| Website: | Website of the Diocese |
The Roman Catholic Diocese of Tubarão (Latin: Dioecesis Tubaraoënsis) is a diocese located in the city of Tubarão in the ecclesiastical province of Florianópolis in Brazil.