Abstract： Objective The hypertension has been confirmed to be one of risk factors of thrombotic complications in atrial fibrillation. However the correlations between blood pressure variation and prothrombotic state in atrial fibrillation have not been reported. The study was designed to disclose the correlations between them. Methods 46 patients with chronic atrial fibrillation and 51 other patients with sinus rhythm as control were enrolled into the study. The indexes of vW factor (vWF), p-selectin (GMP-140), fibrinogen, d-dimer and 24 hrs systolic blood pressure variability (24 h SSD),24 hrs diastolic blood pressure variability (24 h DSD) in atrial fibrillation group were compared with control group. The partial correlations between indexes of prothrom-botic state and blood pressure variability in each group were analysed. Results 1. The 24 h SSD and 24 h DSD in atrial fibrillation group were significant higher than control group, (13.76±4.07mm Hg vs. 11.32±3.19mm Hg, P<0.05) and (10.18±2.57mm Hg vs. 8.47±1.91 mm Hg,P<0.01).2. The vWF and GMP-140 in atrial fibrillation group were significant higher than the control group, (132.00±27.09 iu/dl vs. 104.13±33.79 iu/dl,P<0.01) and (11.12±6.40 ng/ml vs. 7.44±5.73 ng/ml,P<0.05). But the fibrinogen and d-dimer were no significant difference between two groups. 3. In atrial fibrillation group, after controlled by facts of age, blood pressure, heart rate and blood fat, the 24 h SSD positive correlated with vWF(r=0.416, P<0.05),but without obvious correlation with GMP-140 and the 24 h DSD in this group positive correlated with both vWF (r=0.432, P<0.05) and GMP-140 (r=0.378, P<0.05).4. In control group, no significant correlations pres-ent between indexes of blood pressure variability and prothrombotic state. Conclusion Atrial fibrillation with higher blood pressure variability present more significant endothelic impairment and platelet activation. It sug-gests that the risk of thrombotic complications in atrial fibrillation might increase with the augmentation of blood pressure variability.