Four-month-old babies scratching their ears all the time may be related to cerumen impaction, mosquito bites and otitis media. 1. Cerumen impaction: when the cerumen is not cleaned out of the baby’s external ear canal in time, it will cause blockage and uncomfortable feeling of stuffiness, which will make the baby scratching his ears all the time. 2. Mosquito bites: especially in summer when there are more mosquitoes, the baby’s ears are bitten, appearing red, swollen and itchy, and the baby relieves the itching by scratching the ears. 3. otitis media: due to the baby’s Eustachian tube is relatively straight, can be due to nasal congestion, sinusitis and other reasons, caused by the dysfunction of the Eustachian tube, resulting in otitis media, when the ear pain, may appear to scratch the ear. Four-month-old baby is always scratching his ears, there may be other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, give targeted treatment or treatment.