Objective: To investigate the factors for Budd-Chiari syndrome (BCS) with complicated portal vein thrombosis (PVT) . Methods: The clinical data of 28 patients diagnosed as BCS with complicated PVT (PVT group) in the First Affiliated Hospital of Zhengzhou University from January in 2010 to December 2015, and 40 patients diagnosed as BCS without PVT (non-PVT group) in the same period by random pick were retrospectively analyzed. The risk factors for BCS with complicated PVT were screened by univariate analysis and unconditional Logistic regression model. The diagnostic efficiency of each risk factor was analyzed by receiver operating characteristic curve (ROC) and the area under ROC curve (AUC), and their optimal cut-off values were also determined. Results: Univariate analysis showed that the velocity of the portal vein blood flow and the hemoglobin level were significantly lower and the D-dimer (DD) level and splenic thickness were significantly higher in PVT group than those in non-PVT group (all P<0.05); the results of unconditional Logistic regression model analysis identified that DD level, velocity of the portal vein blood flow and splenic thickness were independent risk factors for BCS with complicated PVT (OR=31.67, 0.61 and 1.23, all P<0.05). ROC curve demonstrated that the velocity of the portal vein blood flow had no diagnostic value for BCS with complicated PVT (AUC<0.5), while the AUC of DD level and splenic thickness for prediction of BCS with complicated PVT was 0.724 and 0.673 with the optimal cut-off value of 0.283 μg/L and 49.5 mm, respectively. Conclusion: Serum DD level, velocity of the portal vein blood flow, and splenic thickness are independent risk factors for BCS with complicated PVT, and the possibility of PVT is increased especially in BCS patients with DD level higher than 0.283 μg/L or splenic thickness greater than 49.5 mm.