There are few therapeutic options in relapsed or refractory acute myeloid leukemia patients. CD33 antigen is expressed on approximately 90% of myeloblasts, and gemtuzumab ozogamicin, as a monoclonal antibody directed against the CD33 surface antigen, may be a good target for these patients. Herein, we present a 15-year-old acute myeloid leukemia patient who was resistant at relapse and could achieve remission with gemtuzumab ozogamicin at a total dose of 9 mg/m2, divided into three doses and delivered to hematopoietic stem-cell transplantation; however, the patient relapsed in a short time without application of transplantation.