Acquired hemophilia A leads to severe bleeding and is known to be related to many underlying diseases; however, it has not been reported to occur as a complication of pancreatitis. We present a case of acquired hemophilia A secondary to severe acute pancreatitis. A 76-year-old female developed a hematoma in the lower leg muscle while being treated for severe acute pancreatitis. Blood tests revealed prolonged activated partial thromboplastin time (APTT) and the presence of an autoantibody to factor VIII. The bleeding diathesis was successfully controlled by immunosuppressive therapy. This case highlights the need for careful differential diagnosis for successful management of bleeding disorders as complications of pancreatitis.