We report on 2 cases of chronic relapsing thrombotic thrombocytopenic purpura, in which anti-phospholipid antibodies were also found. The first patient was felt to have the antiphospholipid antibody syndrome, while the second patient had anti-phospholipid antibodies without clinical manifestations of the anti-phospholipid antibody syndrome. We discuss chronic relapsing thrombotic thrombocytopenic purpura and the anti-phospholipid antibody syndrome. Furthermore, we introduce the possibility of an association between chronic relapsing thrombotic thrombocytopenic purpura and the presence of anti-phospholipid antibodies.