Pain on the left side of the nose when pressed is not necessarily cancerous, but may be due to inflammation of the nasal vestibule or an external nasal infection. Pain is usually more pronounced in cases of nasal vestibular inflammation or external nasal boils because of the high tension of the skin here and the pressure caused by the swelling. However, the patient should never squeeze because the infection here can travel retrogradely to an intracranial infection, and anti-inflammatory treatment can usually be given. In case of basal cell carcinoma of the external nose, its main manifestation is the appearance of neoplastic skin of the external nose and the pain is not obvious. In addition, nasopharyngeal carcinoma is also common in the nasal cavity, but the early symptoms of nasopharyngeal carcinoma are blood in nasal aspiration, blood in sputum and nasal obstruction, which do not cause nasal pain. If nasal vestibular infection or external nasal infection occurs, we should pay attention to it and go to hospital for relevant examination to clarify the cause and take symptomatic treatment to ensure the nasal health and restore it to normal state as soon as possible.