The invention discloses a hereditary hearing loss susceptible gene 20 site typing detection kit. The kit comprises PCR amplification primers and single-base extension primers of 1494 C>T and 1555 A>G sites of a mitochondrial gene, 35dleG, 299-300delAT, 235delC, 176-191del19 and 167delT sites of a GJB2 gene, 547G>A and 538C>T sites of a GJB3 gene, and 281C>T, 589G>A, IVS7-2A>G, 1174A>T, 1226G>A, IVS15+5G>A, 1975G>C, 2027T>A, 2162C>T and 2168A>G sites of a SLC26A4 gene. The primers have sequences shown in the formulas of SEQ ID No: 1 to SEQ ID NO: 40. The kit is divided into two groups and is used for amplification and detection of 20 sites so that the accuracy of detection is guaranteed. The kit realizes high efficiency, low cost and high accuracy detection of a hereditary hearing loss susceptible gene type.