We report here the occurrence of phlegmasia cerulea dolens of both lower extremities as a complication of massive deep vein thrombosis in a 37-year-old man with primary antiphospholipid syndrome. The patient had no history of thromboembolic events or any comorbidities. Clinical and laboratory evaluation revealed a strong positive lupus anticoagulant as the unique thrombotic risk factor. In the literature, there is a single case of phlegmasia cerulea dolens as a complication of deep vein thrombosis in an obese woman with a history of thrombosis. We show that phlegmasia may occur in a previously healthy man with positive lupus anticoagulant.