The patient developed Stage Ⅳ transverse colon cancer at the age of 72 years and was treated with an 8-course XELOX regimen(capecitabine and oxaliplatin)every 3 weeks after resection. Six years and 9 months after the end of treatment, at the age of 79 years, WBC levels were found to have markedly increased to 10×104/µL in the patient, and acute leukemia was suspected; subsequently, the patient was hospitalized. Bone marrow was aspirated and analyzed, and the results showed that 95% of leukemic cells were positive for esterase staining. Chromosomal examination revealed t(6 ; 11)(q27 ; q23), ie, the diagnosis of therapy-related acute myeloid leukemia(t-AML)with 11q23 abnormality. CR was achieved by chemotherapy, but the disease soon recurred; the patient died 7 months after the onset of t-AML, with the cause being t- AML with 11q23 abnormality that developed 6 years and 9 months after treatment for colorectal cancer with oxaliplatin and capecitabine without undergoing MDS. Since there is a possibility of leukemia induction following oxaliplatin treatment, more such cases need to be monitored in the future.