| Official Name: | Bermillo de Sayago |
| Nickname: | Bermillo |
| Pushpin Map: | Spain |
| Pushpin Map Caption: | Location in Spain. |
| Subdivision Name3: | Sayago |
| Leader Title: | Mayor |
| Leader Name: | Norberto Núñez Toribio (PP) |
| Area Total Km2: | 189.55 |
| Population Density Km2: | auto |
| Timezone: | CET |
| Utc Offset: | +1 |
| Timezone Dst: | CEST |
| Utc Offset Dst: | +2 |
| Coordinates: | 41.3669°N -6.1121°W |
Bermillo de Sayago (pronounced as /es/) is a municipality located in the province of Zamora, Castile and León, Spain. According to the 2009 census (INE), the municipality has a population of 1,259 inhabitants. It works as the territorial capital of Sayago, leading this comarca but with no official status. Its central position and the fact of a clearly higher population have given the town this role. Furthermore, the municipalities association Sayagua has its headquarters in Bermillo. This organization is a mancomunidad that supplies services like recycling or water through the comarca of Sayago that could not be afforded by the so-little towns in the area.
Geographically, its landscape is a peneplain, as the rest of Sayago (except Duero canyons, that are relatively far away Bermillo).