Dogs with long, flat faces are often called flat-faced dogs, a characteristic of their facial structure that makes their noses and eyes appear flatter relative to the rest of their heads. This trait is common in some dog breeds, such as the Pug, English Bulldog, French Bulldog, and Boston Terrier.

The facial structure of flat-faced dogs may lead to some health problems, including difficulty breathing. , because their nasal passages are short and narrow. Additionally, this structure can easily lead to infections of the skin around the eyes and nose. Therefore, owners of flat-faced dogs need to pay special attention to their health and have regular veterinary check-ups to ensure there are no respiratory or eye-related problems. At the same time, maintaining a proper weight and avoiding overheating are also crucial to preventing these health problems.