The possible causes of pain in the patient’s left sideburn are migraine, trigeminal neuralgia, tumor, trauma, etc., as follows: 1. Migraine, trigeminal neuralgia: the most common is pain in the left sideburn caused by headache, and the cause of headache can be local pain caused by vasodilation and vasoconstriction, commonly known as migraine, or pain due to inflammatory stimulation of nerves, such as trigeminal neuralgia. 2. 2, tumor: it may be some malignant tumor of the brain, benign tumor produced local compression, and the pain symptoms, which is usually accompanied by obvious nausea, vomiting and other symptoms. 3, trauma: left sideburn pain may be due to trauma local pain irritation, serious will also appear local bruising, as well as the emergence of septic, infection and other conditions. If you find pain in the left sideburn, it is recommended that you go to a regular specialist hospital in a timely manner and undergo a systematic examination to clarify the diagnosis.