Although three-month-old babies may have a delayed response to hearing, but the sound will have a certain response. For example, if there is a source of sound baby’s head will be with the direction of the sound up and down, left and right to find, or the emergence of the sound of talking, slamming the door, etc. will jump or wake up; and the baby appeared to be crying, the parents to appease the sound will make the baby quiet down. Therefore, three-month-old babies do not respond to sound is usually not normal, parents are advised to bring their babies to the doctor in time for hearing screening, and if necessary, temporal bone CT or nuclear magnetic resonance. It is recommended that parents take their babies to the doctor for hearing screening, and if necessary, temporal bone CT or MRI, to rule out the presence of intellectual or hearing damage, congenital deafness, neonatal hypoxic-ischemic encephalopathy, and other organic factors. To summarize, parents are advised to bring their babies to the doctor in time to have the cause clarified by the doctor and then give targeted treatment without delay.