[Abstract] Objective To study the common deafness gene mutations in the Han, Hui and Tibetan deafness screening population in Gansu. Methods A total of 1 718 individuals who underwent deafness gene screening at the Medical Genetics Center of Gansu Maternal and Child Health Hospital from January 2019 to December 2021 were collected as research subjects, and 13 mutation sites of 4 deafness genes were detected by deafness gene chip technology. Results Mutations were detected in 197 of the 1 718 deafness screening populations,with an overall mutation rate of 11.46%.Among them,GJB2: 6.17%，SLC26A4: 3.96%，MT-RNR1:0.93%，GJB3:0.17%，compound heterozygous mutation:0.23%.Mutations of GJB2,SLC26A4and MT-RNR1 genes were detected in Han, Hui and Tibetan，among which GJB2 gene had the highest detection rate，followed by SLC26A4 and MT-RNR154.17%，50% and 66.67% respectively.Mutations in GJB3 were only detected in the Han population. The site with the highest mutation frequency among all ethnic groups was the c.235delC site of GJB2，followed by the c.919-2A>G site of SLC26A4.Conclusion GJB2 and SLC26A4 are the main deafness genes in all ethnic groups in Gansu，among which c.235del C and c.919-2A>G are key mutation sites.