| Official Name: | San Mateo de Gállego, Spain |
| Subdivision Name3: | San Mateo de Gállego |
| Area Total Km2: | 72 |
| Population Density Km2: | auto |
| Utc Offset: | +1 |
| Utc Offset Dst: | +2 |
San Mateo de Gállego (Aragonese: Sant Mateu de Galligo) is a municipality located in the province of Zaragoza, Aragon, Spain. According to the 2004 census (INE), the municipality has a population of 3100 inhabitants.