The clinical data of 149 patients who underwent successful laparoscopic splenectomy (LS) between January 2014 and September 2017 were analyzed in the present study. The incidence of portal vein system thrombosis (PVST) in patients with and without cirrhosis was 32.0% and 9.5%, respectively. Multiple logistic regression analysis revealed that the ratio of the postoperative maximum platelet (PLT) count to the preoperative PLT count (r=1.144; P=0.007) was the risk factor for PVST in all patients after LS. Of patients who received prophylactic anticoagulation, 9 and 6 cases of PVST in patients with and without cirrhosis, respectively, (37.5% vs. 85.7%; P=0.037) resolved during hospitalization. In patients who underwent LS, a PLT count increasing to >8 times baseline levels after surgery was the risk factor for PVST after LS, and the sensitivity to anticoagulation postoperatively was significantly higher in patients without cirrhosis than in those with cirrhosis.