The left ear pain may be caused by acute otitis media, ear boils, ear herpes zoster and so on. 1. Acute otitis media: generally refers to acute suppurative otitis media, mainly due to bacterial infection, in the early stage of the ear pain symptoms are mild, as the condition worsens, the ear pain will be more obvious, and will be accompanied by an increase in secretion. 2. Ear boils: mainly refers to the external auditory canal boils, is due to the external auditory canal cartilage part of the skin follicles and the surrounding tissue infection caused by a disease, the causative organisms are mostly staphylococcus aureus, early manifestation of redness, swelling, heat and pain, with the progression of the disease, will form an abscess. 3. Ear herpes zoster: is due to viral infection caused by the disease is often manifested as a burning sensation in the ear or ear boat, and accompanied by pain. Left ear pain may also be caused by auricular suppurative perichondritis, etc. It is recommended to go to the hospital in a timely manner to identify the cause of the targeted treatment.