| São Sebastião da Boa Vista | |
| Settlement Type: | Municipality |
| Mapsize: | 250px |
| Subdivision Type: | Country |
| Subdivision Type1: | Region |
| Subdivision Type2: | State |
| Subdivision Name: |  Brazil |
| Subdivision Name1: | North |
| Area Total Km2: | 1632.218 |
| Elevation M: | 2 |
| Population As Of: | 2020 [1] |
| Population Total: | 26,974 |
| Population Density Km2: | 12.1 |
| Coordinates: | -1.7178°N -49.5408°W |
| Timezone: | BRT |
| Utc Offset: | -3 |
| Postal Code Type: | Postal Code |
| Postal Code: | 68820-000 |
São Sebastião da Boa Vista is a Brazilian municipality located in the state of Pará. Its population as of 2020 is estimated to be 26,974 people. The area of the municipality is 1.632,218 km2. The city belongs to the mesoregion Marajó and to the microregion of Furos de Breves.
The municipality is on the island of Marajó to the northwest of Belém in the delta region where the Amazon and Tocantins rivers empty into the Atlantic Ocean. It contains part of the Terra Grande-Pracuúba Extractive Reserve, a sustainable use conservation unit created in 2006.It is contained within the Marajó Archipelago Environmental Protection Area, a sustainable use conservation unit established in 1989 to protect the environment of the delta region.