AbstractBackgroundHereditary angioedema is a rare autosomal dominant disease, and its correlation between genotype and phenotype seems not to exist. So far, there are very few studies onChinese population. We aimed to establish aChinese genetic database of hereditary angioedema and investigated the potential correlation between genotype and phenotype.MethodAll the eight exons and intron–exon boundaries ofC1 inhibitor gene were detected in 48 unrelated families withHAE. The correlations between genotype and clinical parameters were evaluated byRstatistical software.ResultsThirty‐five different mutations (25 of them were novel) and 7SNPs (3 of them were novel) were identified. Significant difference was found in the level ofC1 inhibitor antigen (P = 0.01793) between different groups of mutational types. The correlation between different groups of mutational types and the level ofC1 inhibitor antigen (0.5047,P = 0.00027) was significant. The different groups of mutational types showed neither difference nor correlations of clinical parameters (severity score and the level ofC1 inhibitor function).ConclusionIt appears that nonsense, frameshift, and mutations onArg466 can cause lower level ofC1 inhibitor antigen than missense and in‐frame mutations; however, it does not affect severity of symptoms.