Acute bilateral renal cortical necrosis is a very rare cause of acute renal failure. We report here for the first time a case related to antiphospholipid syndrome, paraneoplastic of a lung neoplasia. A 46-year-old male smoker without medical history was admitted for acute dyspnea and anuria. Biological examination showed acute renal failure associated with hyperkalemia, high serum lactate dehydrogenase level, and prolonged activated thrombin time (ratio 1.29). Chest radiograph showed a right laterotracheal round lesion. A percutaneous left renal biopsy showed cortical necrosis, and renal arteriography confirmed bilateral cortical necrosis. Blood examination showed antiphospholipid antibodies type anticardiolipin. Chest computed tomographic scan confirmed the presence of a lung tumor. Two years after tumor surgery, the patient was still anuric and on long-term hemodialysis therapy, but antiphospholipid antibody results were negative. This case describes the first association of antiphospholipid syndrome to epidermoid lung cancer, shown by cortical bilateral necrosis. It also emphasizes the utility of renal biopsy in case of an unusual acute renal failure.