| Official Name: | Castrejón de la Peña |
| Subdivision Name3: | Castrejón de la Peña |
| Area Total Km2: | 106.40 |
| Elevation M: | 1120 |
| Population Density Km2: | auto |
| Utc Offset: | +1 |
| Utc Offset Dst: | +2 |
Castrejón de la Peña is a municipality located in the province of Palencia, Castile and León, Spain. According to the 2018 census (INE), the municipality had a population of 360 inhabitants.