A rare association of der(1;7)(q10;p10) with de novo acute erythroblastic leukemia (AML-M6) in a 63-year-old male is reported. While this unbalanced 1;7 translocation, der(1;7), has been reported often in therapy-related myelodysplastic syndrome (t-MDS) or therapy-related acute myeloid leukemia (t-AML), its associations with de novo AML-FAB-M6 have rarely been reported. Although der(1;7) has been reported as a cytogenetic factor for poor prognosis in t-MDS/AML, our patient showed a good response to chemotherapy and obtained complete remission, although longer observation is required to evaluate the prognosis.