We retrospectively investigated hypophosphatemia induced byty rosine kinase inhibitors(TKIs), in patients with chronic myeloid leukemia. Subjects evaluated were 14, 11, and 8 patients who received TKIs(imatinib, dasatinib and nilotinib), respectively, at the Department of Hematology in Ichinomiya Municipal Hospital, between 1st January 2006 and 31st Decem- ber 2016. The incidence of hypophosphatemia was 85.7%(12/14)for imatinib, 18.2%(2/11)for dasatinib, and 37.5%(3/ 8)for nilotinib, and hypophosphatemiaBgrade 3 occurred in 57.1%(8/14)of imatinib- and 9.1%(1/11)of dasatinibtreated patients. Instances of hypophosphatemiaBgrade 3 were not confirmed for nilotinib. Six patients received oral phosphate for hypophosphatemia, and all of these were patients who had been administered imatinib. We confirmed a significant improvement(p<0.05, 95%CI: 0.111-0.989)in serum phosphate levels after administration of oral phosphate, suggesting that it constitutes an effective measure against this situation.