Objective of this study was to identify gene mutation involved in a patient with type 2A von Willebrand disease (vWD). The bleeding time, vWF:Ag, FVIII:C, RIPA and multimeric assay were used for phenotypic diagnosis. All of the 52 exons and the exon-intron boundaries of vWF gene were amplified by polymerase chain reaction (PCR) and direct sequencing was carried out. The results indicated that the levels of vWF:Ag, FVIII:C and RIPA decreased in this patient, the vWF multimer with high and intermediate molecular weight was absent in plasma. The sequencing of genomic DNA revealed a C4738G (L1580V) missense mutation in the vWF gene from the patient. In conclusion, the C4738G (L1580V) missense mutation effecting the form of vWF multimer was responsible to molecular mechanism in this patient with vWD.