Universal newborn hearing screening as an effective measure to prevent and control hearing impairment has been promoted nationwide, and Shanghai in particular, as one of the researchers and promoters of this project, has been at the forefront of universal newborn hearing screening. However, for delayed hearing loss that does not exist at birth, newborn hearing screening cannot detect it in time, but over time, this group of children will gradually develop hearing loss. In other words, delayed hearing loss cannot be ignored in preschool and school-age children. Delayed hearing impairment is defined as hearing loss that occurs gradually during postnatal growth and development, and is currently of concern for preschool and school-age children aged 3-15 years, with the incidence of permanent delayed hearing impairment ranging from 11% to 50%. Hearing loss in preschoolers between the ages of 3 and 6 years old is a critical period for learning and acquiring language skills, and hearing loss during this period can severely impact a child’s ability to communicate and learn later in life, as well as increase the cost of education to society. Unilateral hearing loss has also been found to adversely affect speech development, learning ability, and long-term development, and even mild hearing loss can significantly affect children’s behavior and performance in school. In preschool children, the prevalence of hearing loss ranges from 14.9% to 19.5%, and more than half of these children have conductive hearing loss. Some of the children with conductive hearing loss can regain their hearing within 2-3 months, but some of them have permanent hearing impairment, because these hearing losses are mainly characterized by delayed or gradual or fluctuating, with atypical performance, which is difficult to be detected by parents or teachers in daily life. For example, some children may have difficulty concentrating, answering questions, getting tired easily, or having poor academic performance, which may be caused by hearing loss, but parents and teachers do not easily associate these phenomena with hearing problems. Delayed hearing loss in children has atypical clinical manifestations, but has a significant impact on their speech development, social and academic performance and social behavior, therefore, early detection and early intervention of delayed hearing loss in children should be achieved. It is expected that through joint attention, the prevention and control of late-onset hearing impairment will be raised to the level of prevention and control strategy of congenital deafness, and we will work together to return a better hearing world to children.