Normal people rely on bilateral hearing. The advantages of bilateral hearing over unilateral hearing are as follows: better speech recognition in a noisy background, better recognition of high frequency signals and sound source localization. In the same environment, binaural hearing clearly has an advantage over monaural hearing in that it does not require special attention to achieve a casual unobstructed flow. In general, binaural “stereo” hearing is less labor intensive than monaural “mono” hearing. For patients with severe or profound sensorineural deafness, bilateral hearing reconstruction is usually done with bilateral cochlear implants. The physical and psychological state of children is different from that of adults. There is a period of rapid development and refinement of auditory refinement and language skills – a “critical learning period” that varies from language to language, but is largely concentrated before the age of 3. During this critical learning period, children’s brain potential can be fully utilized for the reception and processing of sound signals, the collection and feedback of linguistic information, and the refinement and stabilization of vocal movements. Children who initiate the auditory-verbal training process earlier during the critical learning period are more likely to acquire proficient and stable verbal skills than children who initiate it later. For children with congenital sensorineural deafness, cochlear implants before the age of 3 still have the opportunity to rapidly develop auditory and speech skills during the critical learning period with unconverted brain function. The benefits are even greater for children with bilateral cochlear implants. In a retrospective study using parent questionnaires, children’s auditory abilities were found to improve significantly with bilateral implants. Children with bilateral implants were more responsive in group settings; they were able to respond more quickly and correctly in everyday situations, and were able to learn language instinctively. In addition, less effort was required in hearing and, according to parents, children were less fatigued after school or returning from kindergarten. Parents report significant benefits of bilateral implants in terms of speech comprehension and growth in the child’s self-confidence. The cochlear implant technology itself has reached the requirement of bilateral implantation effect with the improvement of sound processing technology and surgical technology. Developed countries such as Europe and the United States have accumulated a large amount of experience with bilateral implantation in children, while the research on bilateral implantation in China is limited to a certain extent due to the limitations of concepts and economic conditions. However, with a large number of unilateral implants achieving good rehabilitation results in recent years, there is a need for bilateral implantation to further enhance However, with the good rehabilitation results achieved by a large number of unilateral implants in recent years, there has been widespread interest in bilateral implants to further improve the auditory outcome, the ability to localize sound sources, and the ability to recognize hearing in complex environments such as noise. In addition, with regard to the timing of bilateral staging, the side of the cochlear implant that is unilaterally implanted becomes the “dominant auditory side” after acquiring sound and speech signals. Because of the brain’s biased processing of signals from the sensory system and the functional transformation of the disused cortical areas, the side of the ear that does not have a cochlear implant (or a hearing aid) may experience auditory deprivation while the dominant side is formed. Auditory deprivation usually occurs after good reconstruction of hearing on one side, and irreversible deprivation develops after 3-5 years; for cochlear implant surgery, the interval between implantation on both sides should be controlled within 3-6 months, and no auditory deprivation has been reported on the posterior implant side. Therefore, as far as surgical technique is concerned, the second cochlear implant is not significantly different from the first cochlear implant; the risks and complications associated with the surgery are basically the same; there is no additional surgical difficulty or risk associated with the second implant; the anesthesia time and drug dose required for bilateral simultaneous implantation is shorter than the sum of the two surgeries, and the costs incurred are less; bilateral simultaneous implantation reduces one surgical intervention and the patient In children with congenital sensorineural deafness, the interval between implantations should not exceed 2-3 years. In addition, the coding strategy of the cochlear implant has an impact on the final rehabilitation outcome of children with bilateral implants. For children with bilateral implants, the use of fine structured coding and simultaneous stimulation strategies can synergize bilateral hearing and reproduce the phase difference between the sound signals reaching the two ears in succession, thus improving the localization of sound sources and speech recognition in a noisy context. For children with residual hearing in the low-frequency region, the new soft and super-soft electrodes are more non-invasive and allow for greater preservation of residual hearing after implantation.