The Tibetan Mastiff is a large size Tibetan dog breed. Its double coat is medium to long, subject to climate, and found in a wide variety of colors, including solid black, black and tan, various shades of red and bluish-gray, and sometimes with white markings around neck, chest and legs.

A mastiff is a large and powerful type of dog. Mastiffs are among the largest dogs, and typically have a short coat, a long low-set tail and large feet; the skull is large and bulky, the muzzle broad and short (brachycephalic) and the ears drooping and pendant-shaped. European and Asian records dating back 3,000 years show dogs of the mastiff type. Mastiffs have historically been guard dogs, protecting homes and property, although throughout history they have been used as hunting dogs, war dogs and for blood sports, such as fighting each other and other animals, including bulls, bears and even lions.