Scent hounds are hounds that primarily hunt by scent rather than sight. They are generally regarded as having some of the most sensitive noses among canines.

These dogs specialize in following a smell or scent. Most of these breeds have long, drooping ears. One theory says that this trait helps to collect scent from the air and keep it near the dog's face and nose. They also have large nasal cavities, the better to process scent. Their typically loose, moist lips are said to assist in trapping scent particles.

Most of these breeds have deep, booming voices and use them actively when running, and especially when following a scent trail. Although this can be a nuisance in settled areas, it is a valuable trait that allows the dog's handler to follow the dog or pack of dogs during a hunt even when they are out of sight, such as when following a fox through woodland.