| Castle of Buitrago del Lozoya | |
| Native Name: | Castillo de Buitrago del Lozoya |
| Native Language: | Spanish |
| Coordinates: | 40.9946°N -3.634°W |
| Location: | Buitrago del Lozoya, Spain |
| Architecture: | Gothic, Mudéjar |
| Designation1: | Spain |
| Designation1 Offname: | Castillo de Buitrago del Lozoya |
| Designation1 Type: | Non-movable |
| Designation1 Criteria: | Monument |
| Designation1 Date: | 1931 |
| Designation1 Number: | RI-51-0000721 |
The Castle of Buitrago del Lozoya (Spanish: Castillo de Buitrago del Lozoya) is a castle located inside the walls of Buitrago del Lozoya, Community of Madrid region, Spain.
It was built in the 15th century in Gothic-Mudéjar style. It has a rectangular plan, with seven towers of various shapes (round, pentagonal, square), all in stone. The interior is in ruins.
It was declared Bien de Interés Cultural in 1931.