Question: why does the roof of my mouth hurt really bad?
Answer: Share on Pinterest Sores, injury, and squamous papillomas can cause a swollen roof of the mouth. Most common mouth sores, such as canker sores and cold sores, will appear on the gums, cheeks, or lips. In some cases, they may appear on the roof of the mouth. Sores can cause pain, blisters, and swelling.