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Background Von Willebrand disease (VWD) is an autosomally inherited bleeding disorder with the prevalence of 1 % based on population studies. The disease phenotype is due to quantitative and structural/functional defects in Von Willebrand Factor (VWF) which is a glycoprotein with essential role as a carrier of FVIII in circulation and also it serves the function as hemostasis regulator. VWF is encoded by a large gene located on chromosome 12 which spans 178kb and has 52 exons. Many different mutations are known in VWF gene that can affect the VWD phenotypic features. Materials and Methods In this study we evaluated genetic variations in exon 45 of VWF gene in Iranian patients suffer from VWD from South-west Iran. Materials and Methods: 36 patients diagnosed with VWD (11 males and 25 females), with different ages, from Khuzestan province are participated in the investigation. Exon 3 with the flanking intronic sequences was amplified by PCR and the amplicons were analyzed by sequencing for any genetic changes (mutations and Singl