A 28-year-old woman with a history of a spontaneous abortion developed thrombocytopenia, Coombs-negative hemolytic anemia, and liver dysfunction at the sixteenth week of pregnancy. These findings were compatible with hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome (hemolysis, elevated liver enzymes, and low platelet counts). Moreover, serum anti-phospholipid antibodies were positive, suggesting the association of anti-phospholipid antibody syndrome. An artificial abortion, anti-coagulation therapy, and plasma exchange were performed concomitantly with corticosteroid therapy. She responded to the therapy, a remission was obtained. Anti-phospholipid antibodies may play a role in the pathogenesis of HELLP syndrome.