To identify deafness related gene and provide its prenatal diagnosis to avoid deaf fetus delivery.DNA was extracted from amniotic cells in a pregnant woman close to 21 weeks' gestation, as well as from peripheral blood cells of the pregnant woman, her husband and their two sons. Screening for GJB2 and SLC26A4 gene mutations was firstly performed in the deafness proband (the first son of the couple), and then it was carried out in the fetus and the rest family members.The first child of the family, i.e., the proband, was homozygous in the IVS7-2A > G mutation of SLC26A4, the parents and the second child were carriers of the same mutation, while the fetus had a wild-type form.It is feasible to identify deafness related genes by screening for GJB2 and SLC26A4 mutation, thus providing correct prenatal diagnosis and avoiding deaf delivery of baby.