Aplastic anemia (AA) is a serious hematologic disease characterized by hypocellular bone marrow and deficient production of erythrocytes, granulocytes and platelets. Serious complications such as uncontrolled bleeding and bacteremia can occur. A case of severe AA are presented with dental considerations. A 4-year-old boy had been referred from Seoul National University Hospital for dental examination before the hematopoietic stem cell transplantation (HSCT). Treatments were planned under general anesthesia, due to the poor compliance. Following medical consult, dental treatments were performed after platelet transfusion and antibiotic prophylaxis. Postoperatively, neither significant bleeding nor complictation was observed. On the time of the treatment planning. the anesthesiologist and dentist should perform a complete hematological assessment. It is imperative not only platelet counts but also other leukocyte counts are under safe boundaries. It is mandatory to follow strict aseptic precautios for all anesthetic and surgical maneuvers. In severe thrombocytopenic patients, platelet transfusion should be considered. Also, it is recommended to establish a good oral hygiene.