Objective To study the molecular genetic polymorphism of exons 1,5, 6, 7 of HLA-C gene in Chinese population and evaluate the significance of additional sequencing based typing at exons 1,5, 6, 7 of HLA-Cw gene in clinical HLA matching, Methods A total of 324 individuals were typed at exons 2,3, 4 of HLA-C gene by sequence-based typing. If ambiguities appeared outside of exons 2 -4, we designed a total of 5 in-house sequencing primers and optimized the sequencing reaction, additional sequencing based typing at exons 1,5, 6, 7 was performed to solove the emerging ambiguities. Results In the three hundred and twenty-four samples typed by PCR-SBT at exons 2, 3 and 4 of HLA-Cw gene, 23.8 % (77/324) of the typed samples were assigned the conclusive genotype in four digital level 76. 2% (247/324) of the typed samples were given with the ambiguous allele combination results, in which 73 kinds of ambiguous allele combinations were detected. Increasing the additional sequencing analysis at exons 1, 5, 6, 7 of HIA-C gene, ten frequent ambiguities including Cw* 030201/030202, Cw* 070201/0750, Cw* 040101/0409N/0430, Cw* 0403/0409N/0430, Cw* 080101/0822 could be distinguished. ConclusionsIncreasing the sequencing anlysis at exons 1, 5, 6 and 7 of HLA-Cw gene will help to make clear the ambiguous SBT results and also improve the accuracy of HLA-Cw typing. It shows important significance in clinical histoeompatibility matching.