We present the case of a patient with aplastic anemia (AA) who was treated with eltrombopag. To the best of our knowledge, this is the first report of the disappearance of monosomy 7 after eltrombopag treatment. The patient was a 77-year-old woman with intraoral hematoma and purpura who was diagnosed with very severe AA with a normal karyotype. After combination therapy with rabbit antithymocyte globulin, cyclosporin, and granulocyte-colony-stimulating factor (G-CSF), pancytopenia transiently improved. When pancytopenia worsened again, the patient was administered darbepoetin alfa for renal anemia and danazol. Bone marrow examination showed 2.5% blasts with the karyotype 45,XX,-7[17]/46,XX[3], and 87.0% of marrow cells had monosomy 7, as determined by 7q31 interphase fluorescence in situ hybridization (FISH) analysis. Pancytopenia was considered owing to the evolution of myelodysplastic syndrome, and we stopped G-CSF and darbepoetin treatment. As she refused treatment with a hypomethylating agent, considering her age, eltrombopag was started against refractory pancytopenia after obtaining informed consent. She showed an improvement in pancytopenia and became transfusion independent. After 1 year of eltrombopag treatment, bone marrow examination revealed 0.7% blasts with the karyotype 46,XX[20] and without monosomy 7 clone by FISH analysis. After a further 1 year of eltrombopag treatment with dose tapering, she has achieved a complete response. This case suggested that eltrombopag treatment is not necessarily contraindicated in patients with monosomy 7.