| Type: | Municipality |
| Official Name: | Castrillo de la Reina |
| Postal Code Type: | Postal code |
| Postal Code: | 09691 |
| Area Total Km2: | 15 |
| Elevation M: | 985 |
| Population Density Km2: | auto |
| Utc Offset: | +1 |
| Utc Offset Dst: | +2 |
| Website: | http://castrillodelareina.burgos.es/ |
Castrillo de la Reina is a municipality located in the province of Burgos, Castile and León, Spain. According to the 2004 census (INE), the municipality has a population of 254 inhabitants.