No, shih tzus are not smelly dogs. As house pets, they usually remain clean and don’t have the typical dog smell.
If they ever start to give off a bad odor, it could be because there’s food debris trapped in their facial hair. This can be easily prevented by regular grooming and an occasional wipe with a damp washcloth.
If an odor seems to be coming from other parts of the body, it may be due to skin issues, so a trip to the groomer or veterinarian will diagnose and treat the problem.