Tongue cancer is most common in the tongue margin. One of the important causes of tongue cancer is chronic ulceration of tongue edge caused by long-term mechanical irritation of tongue edge, which is often caused by sharp tooth tip, tooth root, crown and bad prosthesis. If the oral ulcer does not heal for more than two weeks and changes such as bulging around the ulcer occur, the possibility of tongue cancer should be considered, that is, it is appropriate to make pathological section in time to confirm the diagnosis and actively eliminate the carcinogenic factors to prevent or diagnose tongue cancer at an early stage.