Left ear pain may be caused by ear neuralgia, otitis externa, acute otitis media, boils on the external auditory canal, and ear tumors. (1) Ear nerve pain: There are relatively more nerves around the ear, when the left ear is subjected to prolonged overpowering noise or unknown stimuli may cause left ear nerve pain, thus causing left ear pain. (2) Otitis externa: If you use fingernail or ear-digging spoon to dig into the left ear blindly, it will easily cause damage to the skin of the external auditory canal of the left ear, resulting in localized skin infection and thus causing pain in the left ear. (3) Acute otitis media: When the middle ear cavity of the left ear is infected, pus can be generated continuously to compress the tympanic membrane, thus causing pain in the left ear. (4) External auditory canal boil: a limited purulent inflammation of the skin of the left external auditory canal. As the subcutaneous soft tissue of the external auditory canal is small, the skin and cartilage membrane are close to each other, the inflammatory swelling stimulates the nerve endings, causing severe pain. (5) Ear tumor: If malignant tumors appear in the left ear canal and middle ear cavity, with the development of the tumor infiltrating the surrounding tissues, it can cause pain. People with pain in the left ear should go to the hospital in time to find out the cause of pain in the left ear and treat the cause in order to avoid delaying the condition.