Redness, swelling and pain in the external auditory canal may be caused by otitis externa, auricular suppurative chondritis, external ear eczema and other diseases. 1. Otitis externa: Otitis externa is mainly due to bacterial and other pathogenic infections, patients will appear in the external auditory canal skin edema, skin surface oozing, pain, edema, redness, flaking and other symptoms. When the inflammation of the external auditory canal spreads to the auricle, it can cause redness, swelling and pain in the auricle. 2. Auricular suppurative chondritis: Auricular suppurative chondritis is mainly caused by the spread of infection in the outer ear and neighboring tissues, and the main symptoms of patients are erythema of the auricle, redness, swelling, burning sensation, and pressure pain. Patients with auricular suppurative chondritis also have symptoms such as elevated body temperature, headache, irritability, and muscle and joint pain. 3. Eczema of the outer ear: the etiology and pathogenesis of eczema of the outer ear are not clear, and it is considered to be related to metamorphosis. Patients will have itching, burning sensation, skin redness, swelling, flaking, headache, etc., but also oozing, crusting and other symptoms. Patients with symptoms of redness, swelling and pain in the external auricle should consult a doctor for a systematic examination to clarify the diagnosis, and follow the doctor’s instructions to standardize the treatment.