For children who are deaf, why is the importance of early cochlear implantation particularly emphasized? From an anatomical, auditory physiological and developmental point of view, the earlier the cochlear implant is implanted, the better the auditory-linguistic rehabilitation will be. 1. It is well known that the maturation of the human auditory center occurs around the age of 3. In particular, during the second infancy, from about 6 months to 2 years of age, there is an explosion of synapses in the left temporal lobe. During the period of rapid development of the auditory center, if the auditory center does not receive long-term effective stimulation of sound signals, developmental delay or reduction or even atrophy of neurosynapses may occur. Therefore, if hearing is acquired after the rapid developmental period of the auditory center, the postoperative rehabilitation period will be prolonged and the effect of auditory language rehabilitation will be affected, even if efforts are made to conduct auditory language rehabilitation training. 2. On the other hand, since the human cochlea is basically shaped after birth, its structure, length and height are basically the same as those of adults. Such anatomical characteristics make it possible for infants and children to undergo cochlear implant surgery. In response to a large number of clinical analyses and summaries of cochlear implant surgeries in children, it is concluded that the earlier the cochlear implant is performed, the better the auditory-speech function. 1. The study found that children with cochlear implants before the age of 2 years not only scored higher on auditory-verbal tests, but also achieved optimal auditory-verbal function earlier compared to children with cochlear implants after the age of 2 years. 2. The study also found that even children who were implanted before the age of 4 still had irreversible changes and deficits in their auditory centers and their post-cochlear implant results were not as good as those of children who were implanted earlier. Therefore, children who are deaf should receive a cochlear implant as early as possible once the diagnosis is clear and the surgical target is met, as this is a wise way to achieve better auditory-verbal outcomes. Cochlear implantation before the age of 2 years, preferably 1 year and earlier may result in the most optimal auditory-speech outcome.