In general, the Yorkshire Terrier breed does not have any breed related reasons for having a bad smell. However, there are reasons why a bad odor would permeate through the coat, ears, mouth and other areas. read more
What does make them smell might be their teeth (as someone said) because they do need to be cared for, brushed, etc. My dog was a rescue Yorkie and most of her teeth had to be pulled because she was so neglected. read more