The Yorkshire Terrier, though a toy breed, still retains much of its Terrier ancestry in terms of personality. Though personalities differ from dog to dog, they are generally intelligent, independent and spunky. Yorkies, especially males, are very territorial and are known for their disregard for the limitations of their own size. They will often attack much larger dogs despite their extreme size disadvantage. Yorkies typically get along well with cats and other dogs, and love to play together. However, they are terriers, and even an old, sedentary lap dog may eagerly hunt rodents.

Because they are so small, they are easily injured; They usually get along well with children, but may be endangered if kept in the house with an undiscerning or abusive person, especially a child. Also, despite their small size, if attacked or continually provoked, like all dogs, they pack a surprisingly powerful bite. Yorkshire Terriers tend to be more difficult to train than some of their canine cousins; however, this difficulty is considered to be a result of the breeds characteristic prey drive rather than any major deficiency of intelligence as they were bred to work without human intervention.