| Type: | municipality |
| Subdivision Name3: | Secastilla/Secastella |
| Area Total Km2: | 47 |
| Elevation M: | 612 |
| Population Density Km2: | auto |
| Utc Offset: | +1 |
| Utc Offset Dst: | +2 |
Secastilla (pronounced as /es/), in Aragonese: Secastiella, is a municipality located in the province of Huesca, Aragon, Spain. According to the 2018 census (INE), the municipality has a population of 146 inhabitants.