A 74-year-old man diagnosed with idiopathic thrombocytopenic purpura (ITP) nine years ago, was referred to our hospital because of cecal cancer. After the infusion of a high dose of gamma globulin preoperatively, iliocecal resection and splenectomy were performed. His blood platelet count did not increase much postoperatively, therefore, adjuvant chemotherapy was not performed. After one year, metastases of the liver, lung, and lymph node of the para aorta were revealed by CT. Since high-dose steroid therapy was effective temporarily, we decided to perform mFOLFOX chemotherapy. After that, his blood platelet count increased gradually to the normal range, and steroid therapy was no longer required. His blood platelet count remained in the normal range after changing the mFOLFOX chemotherapy to FOLFIRI and XELOX chemotherapy. Some studies reported the effect of chemotherapy on refractory ITP, but no one has reported the effect of chemotherapy for colon cancer refractory to ITP. We concluded that chemotherapy for colon cancer can be indicated for refractory ITP.