| Jurisdiction: | Diocese |
| Sinop | |
| Latin: | Dioecesis Sinopensis |
| Country: | Brazil |
| Rite: | Latin Rite |
| Established: | 6 February 1982 (years ago) |
| Cathedral: | Catedral Santo Antônio |
| Area Km2: | 191,000 |
| Population: | 650,000 |
| Population As Of: | 2014 |
| Catholics: | 534,000 |
| Catholics Percent: | 82.2 |
| Map: | ProvinciaEclesiasticaCuiaba.jpg |
The Roman Catholic Diocese of Sinop (Latin: Dioecesis Sinopensis) is a diocese located in the city of Sinop in the ecclesiastical province of Cuiabá in Brazil.