OBJECTIVES:  To examine the health care utilization and costs incurred by patients diagnosed with myelodysplastic syndrome (MDS) in the US Medicare population. METHODS: Patients diagnosed with MDS (International Classification of Diseases, 9^th Revision, Clinical Modification diagnosis codes 238.72-238.75) were identified from the 100% national Medicare data population from 01JAN2009-31DEC2013. The first diagnosis date was designated as the index date. Patients were required to have continuous medical and pharmacy benefits 12 months pre- and post-index date. Study outcomes included demographic and clinical characteristics as well as health care costs and utilization for patients diagnosed with MDS. RESULTS:  A total of 166,545 MDS patients were identified. The mean age was 80 years. The majority of patients were female (53.42%), white (88.06%), and resided in the South (38.99%) or Midwest (24.18%) US region. The mean Charlson Comorbidity Index scores were 4.99 (standard deviation = 3.49). The most commonly diagnosed comorbid conditions included hypertension (78.36%), and diabetes mellitus (33.07%). Health care utilization was assessed, including the proportion of patients with inpatient (26.89%), emergency room (ER; 28.00%), physician office (94.00%), outpatient hospital (80.81%), skilled nursing facility (SNF; 8.07%), hospice (2.04%), home health agency (HHA; 16.27%), and durable medical equipment (DME; 39.91%) claims. Patients with MDS incurred higher mean health care costs, including inpatient ($6,482), ER ($285), physician office ($4,805), outpatient hospital ($9,237), SNF ($1,720), hospice ($429), HHA ($1,004), DME ($511), Part D pharmacy ($2,496), and total costs ($26,968). CONCLUSIONS:  During a 12-month period, Medicare patients diagnosed with MDS incurred substantial health care utilization and costs.