The antiphospholipid syndrome (APS) has been associated with portal vein thrombosis (PVT). This study explored the contribution of antiphospholipid antibodies (aPL) to PVT in cirrhotic and noncirrhotic patients. Patients and methods: A total of 50 patients with liver cirrhosis and PVT, 50 patients with liver cirrhosis without PVT, 50 consecutive PVT without liver cirrhosis, and 50 controls. aPL tests: lupus anticoagulants (LAs), immunoglobulin G (IgG) anti-cardiolipin antibodies (aCL), IgG anti-beta-2-glycoprotein-I (β2GPI), and IgG β 2GPI-complexed with oxidized low-density lipoprotein antibodies (ox-LDL). Results: Lupus anticoagulants were negative in all patients. A titre of IgG aCL >40 IgG phospholipid units (GPL) was present in 2% of patients with liver cirrhosis and in none of the other groups. In all, 4% of patients with PVT without cirrhosis were positive for IgG β2GPI in the absence of any other positive aPL and labelled as primary APS. Conclusions: aPL play no role in PVT associated with liver cirrhosis but can be tested in idiopathic PVT.