Abstract: Objective To investigate the relationship between circulating von Willebrand factor（vWF） and microalbuminuria in essential hypertensive patients, and to evaluate the possible determinants of this association. Methods Circulating vWF, a indicator of endothelial dysfunction and 24 hours urinary albumin excretion were measured in 55 patients with essential hypertension.\ 31 healthy subjects matched age, sex, weight index served as controls. The blood pressure（BP）, body mass index（BMI） and serum lipid, serum creatine, t PA, PAI-1, Fbg concentrations were measured. Results vWF values were higher in hypertensive patients without microalbuminuria and controls, vWF were correlated with urinary albumin excretion.\ Blood pressure positively related with both vWF and urinary albumin excretion. Fibrinogen was raised in microalbminuria and correlated with vWF level. Conclusions Microalbuminuria and increased vWF levels usually coexist in patients with essential hypertension, indicating that microalbuminuria reflects a systemic dysfunction of vascular endothelium function. Hypercoagulability was associated with essential hypertensive patients complicated with microalbuminuria.