Lupus anticoagulant (LA) and anticardiolipin antibody (aCL) are circulating immunoglobulins against phospholipids which can result in prothrombotic conditions We present our experience of 45 LA and/or aCL positive stroke patients. I A was tested with a combination of aPTT mixing test, thromboplastin inhibition test, and kaolin clotting time. aCL was measured with ELIZA. There were 33 males and 12 females with their ages ranging from 20 to 76(mean 518) Fifteen patients did not have risk factors for stroke, while 13 had a single, and 17 had multiple risk factors. Hypertension (20 cases) and smoking (14 cases) were the important risk factors while cardiac diseases were found in 9 patients. All patients underwent head CT and/or MRI, which showed multiple infarcts in 18, single infarct in 22, intracerebral hemorrhages in 4, cortical venous infarct in 1 and sagittal sinus thrombosis in 1. Among patients with cerebral infarct, 23 had infarcts in carotid territory, only 7 of whom had large infarcts involving the cerebral cortex. Eleven had strokes in vertebro-basilar territory, and 6 had in both. Overall, 22 patients had relatively small infarcts in carotid territory. Angiogram was performed in 23 patients, which showed normal findings in 14 (most did not have risk factors), internal carotid narrowing or occlusion in 2, proximal MCA narrowing in 2, occlusion of vertebral artery in 1, multiple MCA and ACA occlusion in 1, and venous occlusion in interestingly, one patient showed occlusion of proximal branches of aorta consistent uith Takayasu's disease We conclude that relatively small multiple or single ischemic lnfarcts with negative angiographic findings are the most characteristic findings of antiphospholipid antibody associated stroke, while occasionally observed marked angiographic abnormalities or large cerebral embolic strokes are usually associated with other risk factors Antiphospholipid antibodies seem to play a role in the dlevelopment of cerebrovascular diseases in Korean patients especially in the young age.