Objectives - The pathogenesis of Behcet's disease (BD) is closely related to endothelial cells, leucocyte functions and autoimmunity. The aim of this study was to investigate circulating selectin adhesion molecules, which are known to play a significant part in the immune response especially by regulating interactions of the leucocytes with endothelium, in BD. Methods - Plasma E-, L-, and P-selectin concentrations were evaluated in 11 patients with widespread BD (group I), 10 cases with merely mucocutaneous involvement (group II) and 15 age and sex matched healthy control subjects. The patients were newly or previously diagnosed cases not taking any drug for BD. Results - Plasma concentrations of all selectins were significantly higher in group I compared with group II. E-selectin and P-selectin were significantly increased in each subgroup of patients compared with the healthy controls. L- selectin concentrations were higher than the controls only in group I. Conclusions - Increases in the selectins in BD may be a direct consequence of the leucocyte, endothelium and platelet activations observed during the disease process. However, abnormal/increased selectin expression to various triggers should also be considered. More prominent increases in patients with extensive disease suggest that circulating selectin concentrations are related to disease severity.