Genetic diagnosis of deafness has far-reaching significance in clarifying the cause of deafness and preventing the occurrence of deafness. Since 2003, through the established deafness genetic resource collection network, nearly 4000 Chinese deafness disseminated cases and family lines have been collected in 28 regions of China. A large-scale molecular epidemiological survey of sensorineural deafness population was conducted in different regions of China with a unified strategy and methodology. The study revealed that: 1. The etiology of deafness in the Chinese population: genetic factors accounted for about 60%; unknown etiology (environmental or other causes) accounted for 40%. 2. In the population with severe to profound deafness, it was concluded that: (1) 3.43% of deafness was caused by maternally inherited mitochondrial gene 1555A>G mutation; (2) 21% of deafness was associated with GJB2 gene; (3) 15% of deafness was associated with SLC26A4 gene related to vestibular canalicular and inner ear malformations. GJB2 and SLC26A4 were the first and second most common common causes of deafness in the Chinese population, respectively. 3. Through the study, we mapped the common gene mutations in Chinese deafness population, calculated the frequency of each mutation type of common genes such as GJB2 and SLC26A4 after rigorous statistical analysis, and established the hotspot mutations of each gene in Chinese population, which guided the establishment of deafness screening procedures and the establishment of genes and mutation loci in deafness gene diagnostic microarray in practice. The aim of this work is to make the deafness genetic diagnosis procedure scientific and efficient, and to move toward the goal of large-scale, high-throughput and low-cost screening of deafness genes.