To identify the level of von Willebrand factor (vWF) in dengue infection, especially severe DHF, and correlate the increase in vWF with thrombocytopenia, children admitted with dengue fever/DHF were examined for hemoglobin, hematocrit, platelet, and vWF for three consecutive days. Anti-dengue IgM and IgG were determined. Correlations between vWF and thrombocytopenia were analyzed using multivariate analysis. Forty-one patients were eligible for the study; of whom almost three fourths had a secondary infection, as proved serologically. At the beginning of the study, a high level of vWF along with a low platelet count were seen, which seemed to fit the hypothesis that an increase in vWF in the serum will be followed by a decrease in platelets, as a result of the platelet aggregation process in the peripheral blood vessels, predisposed by the immune complex events in DHF. Observations for three consecutive days revealed significant changes of vWF levels (p = 0.000) as well as platelet counts (p = 0.002). However in the context of dengue infections, these changes did not correlate well (p = 0.988). Could there have been a significant correlation if cases were followed for a longer period of time? Being a part of a more comprehensive study, it appeared that in patients with dengue infections, vWF and platelets were not the only factors involved in bleeding, indicating that activation of endothelium is one factor in a multifactorial process.