| Country of origin: | Spain |
| Registries: | UKC, CKC |
| Occupation: | Livestock guardian |
| Size: | 55–70kg (121–154lb), 72–82cm (28–32in) |
| Longevity: | 10 to 12 years; some to 14 years |
| Exercise: | Low to moderate |
| Training: | Easy; socialization required |
| Grooming: | Sheds and drools |
| Colors: | Variety of colours |
Rarely seen outside Spain, the Spanish Mastiff (Mastin de Extremadura or Mastin de la Mancha) was taken to Spain by Phoenician traders over 2,000 years ago to what was then arid wasteland, but is today the wheat belt. The Spanish Shepherd’s Association records that this bulky breed, a great saliva dribbler, has been protecting livestock from wolves for at least 600 years. Today, the majority of these dogs guard homes rather than livestock and, although males in particular can be aggressive with other dogs, they make reasonable family companions, and have surprisingly small exercise demands. Descendants of Spanish mastiffs exist throughout the regions of the former Spanish Empire.
Extra-large dogs such as the Spanish Mastiff grow enormously quickly, and this has led to myths about their unique nutritional needs during puppyhood. Contrary to what is sometimes advised, these dogs do not need calcium supplements to grow healthy bones. In fact, adding extra calcium to an already balanced diet may actually cause developmental bone problems.