1. Exact audiological and medical diagnosis: The audiological and medical diagnosis must be clear (including the integrity of the middle ear, inner ear and auditory nerve, cochlear structures; auditory neuropathy, large vestibular conductance syndrome and other metabolic and genetic disease syndromes, etc.). 2.Obtain accurate and full frequency band: (at least 0.5k, 1k, 2k and 4kHz points should be included) hearing loss degree value (remember never to use the results of multi-frequency steady state directly), i.e. obtain accurate predicted hearing curve of both ears that can be used for hearing aid fitting. 3. Medical professional fitting: In addition to hearing aids and audiology, hearing aid fitting also involves a comprehensive medical assessment of the baby. Such as the diagnosis of developmental delay, lingual tethering, large vestibular conduit syndrome, auditory neuropathy and cerebral palsy and intelligence, cytomegalovirus infection, pediatric auditory development and mental development, etc. 4.Bilateral hearing loss must be bilaterally tested and fitted with hearing aids. 5.Avoid non-intervention and insufficient intervention: When audiological subjective and objective examinations do not lead to a response, it is often thought that there is no residual hearing, in fact, most of them have some residual hearing, therefore, early (less than 1 year old) should not give up the fitting of hearing aids. 6. Avoid excessive intervention. We already know that there is a problem of delayed hearing development and test error (test must be repeated twice) (about 7%), especially in patients diagnosed with mild to moderate hearing loss. The problem of overdiagnosis in early intervention (less than six months of age) can occur, and overdiagnosis will inevitably lead to excessive intervention, which must be done in moderation. 7. Choose a hearing aid with high performance as much as possible. High performance hearing aids have the advantages of high fidelity of expanded sound, wide sound range and fast and strong sound processing ability. 8, hearing aid fitting must be early, and at the same time adhere to the family-oriented auditory and speech rehabilitation training. 9, hearing aid fitting after verification and effect assessment, without verification and effect assessment of hearing aid fitting is dangerous. 10.The correct use and maintenance of hearing aids and earmolds and regular follow-up visits.