The Pastore Fonnese is a rare Sardinian breed, believed to be descended from ancient war mastiffs of Roman consul Mark Pomponio Matone which were reportedly crossed with local bearded sheepdogs and hounds. Rooted in old Sylvan, as well as Assyrian, Persian and Greek Molosser blood, the original Fonnese Mastiffs were used in war campaigns in Africa and for personal protection duties, but were also traditionally employed as livestock guardians and herders. After those original wardogs became assimilated into the local farm sheepdog population of Sardinia, the present shape of the Fonnese Sheepdog became established and had remained virtually unchanged for almost 2000 years, thanks to the relative isolation of its home region and the unwillingness of its breeders to sell their puppies to outsiders. Although there is some confusion concerning this Molosser, it is safe to say that this is not the same dog as the Dogo Sardo, which is a typical bully breed of the old Cane E Presa Italiano type, similar to the Cane Corso. There is also a separate smooth-coated variety of the Pastore Fonnese, which is a result of crossing the Dogo Sardo with the Fonnese Sheepdog and known as the Mastino Fonnese, but is sometimes also mistakenly listed under the Dogo Sardo name, creating even more confusion. The Pastore Fonnese is a rugged and powerful working dog, looking like a smaller South-Russian Ovcharka or a larger Bearded Collie, valued for its resilience and serious personality. This is an intelligent and intuitive dog, completely devoted to its owner, but very suspicious of strangers and aggressive towards other dogs. Because of its independent nature and overly protective attitude, the Fonnese Sheepdog is rarely seen in urban environments, but in recent years there have been reports of efforts to standardize and promote the breed in its homeland. Large-headed, muscular and well-boned, this is a strong and athletic Molosser.

The rich coat is fairly rough and weatherproof, usually gray, black, brindle or salt-n-pepper in colour, most often with a white spot on the chest. Average height is around 24 inches, but larger dogs exist.