| Official Name: | San Antonio del Sur |
| Settlement Type: | Municipality |
| Subdivision Type: | Country |
| Subdivision Name: | Cuba |
| Subdivision Type1: | Province |
| Subdivision Name1: | Guantánamo |
| Area Total Km2: | 585 |
| Population As Of: | 2022 |
| Population Total: | 25,752 |
| Population Density Km2: | auto |
| Timezone: | EST |
| Utc Offset: | -5 |
| Coordinates: | 20.0569°N -74.8078°W |
| Elevation M: | 5 |
| Area Code: | +53-21 |
| Website: | https://sanantonio.gob.cu/es/ |
San Antonio del Sur is a municipality and town in the Guantánamo Province of Cuba. It is located on the southern coast of Cuba, bordering the Windward Passage to the south.
In 2022, the municipality of San Antonio del Sur had a population of 25,752.[1] With a total area of 585km2,[2] it has a population density of 44/km2.