Antiphospholipid antibodies may play and important role in the pathogenesis of retinal vascular occlusions; investigated the prevalence among 33 patients with retinal vein and artery occlusions and 80 controls. Prevalence was 33% and 5% respectively. Ophthalmic examination and fluorescein angiography showed that occlusions were due to ischaemic events. The 11 patients were diagnosed with antiphospholipid syndrome: 9 patients were treated successfully with laser photocoagulation and anticoagulant and anti-aggregant therapy. Two patients with antiphospholipid antibodies associated with resistance to activated protein C had unfavourable outcomes. Our results suggest a correlation between antiphospholipid syndrome and retinal vein occlusions; we recommend a systematic search for antiphospholipid antibodies in occlusions of unexplained origin and laser photocoagulation treatment and long-term oral anticoagulant and anti-aggregant therapy.