Objective:To investigate the influencing factors for portal vein thrombosis after laparoscopic splenectomy and azygoportal disconnection (LSD).Methods:The retrospective case-control study was conducted. The clinicopathological data of 106 patients with portal hypertension, type B viral hepatitis and cirrhosis who were admitted to Clinical Medical College of Yangzhou University from September 2014 to January 2017 were collected. There were 83 males and 23 females, aged (51±11)years. All patients underwent LSD. Observation indicators: (1) incidence of postoperative thrombosis and treatment; (2) influencing factors for portal vein thrombosis after LSD. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Count data were described as absolute numbers, and comparison between groups was conducted using the chi-square test. Univariate analysis was conducted by corres-ponding statistic methods. Multivariate analysis was conducted by Logistic stepwise regression model with forward method. Results:(1) Incidence of postoperative thrombosis and treatment. All 106 pati-ents were followed up in the postoperative 1 month. During the follow-up period, 35 patients had thrombosis occurred in main and intrahepatic branches of portal vein, including 23 cases with thrombosis occurred in main portal vein, 1 case with thrombosis occurred in intrahepatic right branches of portal vein, 5 cases with thrombosis occurred in main and intrahepatic right branches of portal vein, 5 cases with thrombosis occurred in main and intrahepatic left branches of portal vein, 1 case with thrombosis occurred in intrahepatic left branches of portal vein. Of the 35 patients with portal vein thrombosis, 17 cases were treated with warfarin and 18 cases were treated with aspirin. (2) Influencing factors for portal vein thrombosis after LSD. Results of multivariate analysis showed that preoperative portal vein diameter was an independent factor influencing portal vein thrombosis after LSD ( odds ratio=1.559, 95% confidence interval as 1.200-2.027, P<0.05). Conclusion:Preoperative portal vein diameter is an independent factor influencing portal vein thrombosis after LSD .