A novel mutation of vascular endothelial growth factor receptor gene (VEGFR-3), was identified in a four-generation Chinese family with hereditary lymphedema type I (HL-I). Genetic linkage analysis was performed on the known genetic locus for HL-I with a panel of polymorphic markers, and then mutations were screened out by direct sequencing. By genotyping, the family showed the linkage to HL-I locus on 5q35.3. Mutation screening analysis of the exons encoding the intracellular kinase domains of VEGFR-3, revealed a novel missense mutation D1055V. This mutation cosegregated with the disease phenotype in the family and was not found in 100 normal controls. This finding has expanded the spectrum of the VEGFR-3 gene mutations causing HL-I, and will be useful for further genetic consultation and genetic diagnosis.