OBJECTIVES: To examine health care utilization and costs associated with acute myeloid leukemia (AML) among patients in the Medicare population. METHODS: Medicare patients aged ≥65 years with an AML diagnosis (International Classification of Disease, 9^th Revision, Clinical Modification [ICD-9-CM] code: 205.xx) were identified from 01/01/10 to 12/31/14. The first AML treatment date within 30 days after the incident diagnosis was the index date. Patients with an ICD-9-CM code for relapse (205.02), or claims of chemotherapy after a ≥120-day treatment-free gap, were considered relapse cases. Patients were required to have continuous enrollment 12 months before the initial AML diagnosis. Patients with blood cancer, chemotherapy, radiotherapy, or AML-related surgery prior to the initial diagnosis were excluded from the study. Health care costs and utilization of patients with only first-line therapy (Cohort A), and relapse patients with first- and second-line therapies (Cohort B) were examined descriptively. RESULTS: A total of 6,281 and 1,726 patients were included in Cohorts A and B, respectively. During the first-line therapy, the percentages of patients with ≥1 inpatient, emergency room (ER), and hospice visits were 89.1%, 35.6%, and 39.7% in Cohort A, respectively (mean follow-up: 247 days). During first-line therapy (mean 396 days), the percentages of patients with ≥1 inpatient, ER, and hospice visits were 88.9%, 42.0%, and 2.5% in Cohort B, respectively. Per patient per month (PPPM) costs for inpatient admission ($10,451), outpatient ($6,213), and total costs ($17,622) were high. During second-line therapy (mean 256 days), the percentages of patients with ≥1 inpatient, ER, and hospice visits were 75.2%, 32.2%, and 40.9% in Cohort B, respectively. PPPM costs for inpatient admission ($21,982), outpatient ($6,178), and total costs ($29,718) increased compared with the first-line period. CONCLUSIONS:  AML patients in the Medicare population incurred significant health care utilization and costs – especially during the relapsed period.