Mouth ulcers that leave a pit may be periglottic aphthous ulcers, tuberculous ulcers, cancerous ulcers and so on. Treatment mainly includes local glucocorticoid therapy, anti-tuberculosis treatment, surgical excision and so on. 1. Most oral ulcers are defects in the surface layer of the mucous membrane, shallow ulcers, and generally do not leave a pit after healing. If a pit is left, the most common is that of heavy recurrent aphthous ulcers, also known as glandular perioral ulcers. Generally need local glucocorticoid treatment, in the base of the ulcer hit injection glucocorticoid, such as prednisolone. 2. Tuberculous ulcer treatment is mainly anti-tuberculosis treatment, such as the use of rifampicin and isoniazid. The drugs should be used under doctor’s guidance. 3. Cancer ulcers mainly require surgical resection, radiation therapy and chemotherapy if necessary. Mouth ulcers left a pit is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment, the use of drugs need to follow the doctor’s instructions.