Furry Diary

Spanish Mastiff

Also called Mastín Español, Mastín Leonés, Mastín Extremeño, Perro merinero

Recognised breedFCI group 2Short profile

From Spain, where it guarded migrating Merino flocks across the country's old livestock routes.12

At a glance the quick version

Weight, male80 to 120 kg213
Weight, female65 to 80 kg213
Height, male77 to 85 cm12
Height, femalefrom 72 cm12
Sizegiant

Weights from Wikipedia; the FCI and UKC standards set no weight.

calm and self-assured
deeply loyal to family and flock
natural, steady guardian
132

Coat and looks how to spot one

medium-length double coat

A thick, dense coat of medium length that lies smooth over the body. It is a little shorter on the legs and grows longer and softer on the heavy tail. The body is long, deep and very muscular under a big, broad head with loose skin at the throat.13

Coloursyellowfawnredblackwolf-greydeer-colouredbrindleparti-colouredany of these with white markings13

Personality what they are like

A quiet, dignified giant that knows its own strength. It is gentle and affectionate with its people and tends to be reserved with strangers, turning serious only when it senses a real threat to home or herd.132

Daily activity how busy a day looks

Moderate. Bred to walk long distances beside moving flocks rather than to sprint, so steady daily walks and room to patrol suit it better than intense exercise.12

Grooming and care the hands-on bits

Weekly brushing keeps the dense coat in good order, with more frequent brushing when it sheds. Early, gentle and consistent training and socialisation matter for a dog of this size.32

Home where they are happiest

Best in a home with a large, securely fenced garden or rural land to watch over. Its size and guarding instinct make a small flat a poor fit.32

Food basics what goes in the bowl

A quality diet portioned for a giant breed, with growth kept slow and steady in puppies and body weight kept lean in adults.2

Company who they like around

Very attached to its family and happiest with people or animals to look after. Early socialisation with other dogs and visitors helps it stay relaxed.23

The story where it all began

Big guardian dogs have worked on the Iberian Peninsula for many centuries. From the Middle Ages the Mastín walked with Merino sheep on their seasonal journeys across Spain, protecting them from wolves and other predators, often with little direction from shepherds. It still works as a livestock and farm guardian today.123

Fun facts for the dinner table

  1. 1

    Working Mastines traditionally wore heavy metal collars fitted with spikes to protect their throats from wolves.2

  2. 2

    World Wide Fund for Nature data cited on Wikipedia reports a 61% drop in livestock predation when flocks are guarded by Mastines.2

  3. 3

    The breed was often left to guard flocks on its own during migrations, making its own decisions without a shepherd close by.3

Recognised by the official bits

FCI
Standard no. 91 (Mastín Español), Group 2, Section 2.2 Molossoid, mountain type; standard published 26.05.1982. Wikipedia notes a breed standard first set in 1946.1
UKC
Recognised 1 July 2006 in the Guardian Dog Group.3
AKC
Listed on the AKC breed pages (Foundation Stock Service breed).4

The care rhythm Furry Diary remembers it for you

A typical home-care rhythm for a Spanish Mastiff. It is our own starting plan, not a vet's advice, and you can change every line in the app.

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Where this comes from

Every breed page shows where each fact comes from. If we got something wrong, sorry, we are pet people, not a science magazine. Tell us at [email protected] and we will fix it.

  1. FCI Standard No. 91, Mastín Español fci.beused for origin, recognition, height, coat, colours, temperament, history
  2. Wikipedia: Spanish Mastiff en.wikipedia.orgused for other names, weight, height range, history, fun facts
  3. UKC Spanish Mastiff breed standard ukcdogs.comused for UKC recognition, coat, colours, temperament, history
  4. AKC: Spanish Mastiff akc.orgused for AKC listing

Checked 2026-09-30. Text is written in our own words from these sources.