OBJECTIVES: Acute Myeloid Leukemia (AML) disproportionately affects older patients. Treatment often requires lengthy hospitalizations, including those for chemotherapy administration and follow-up. Recent studies suggest that outpatient management following chemotherapy may be safe and reduce costs, but information on the characteristics of AML hospitalizations is limited.  The objective of this study is to characterize costs and length of stay (LOS) for hospitalizations in the US for older adults with AML. METHODS: We used the 2013 Medicare Inpatient Limited Data Set (LDS) file to identify hospitalizations with a principal or secondary diagnosis of AML (ICD-9 205.0). We grouped hospitalizations by the Diagnosis Related Group (DRG) used for reimbursement and calculated mean payments and LOS by DRG. We identified hospitalizations where chemotherapy was administered using ICD9 procedure codes V58.1 and 99.25.   RESULTS: Of 12,524 hospitalizations with AML as a discharge diagnosis, AML was the principal diagnosis for 6,655 (53.1%). Mean payment for these hospitalizations was $37,198; average LOS was 13.6 days. These hospitalizations included 2,219 ICU stays with mean ICU LOS of 9.6 days. Nearly all principal AML diagnosis hospitalizations (6,563) were assigned to one of four DRGs, with payments and LOS ranging from $10,111/4.8d to $97,797/25.5d; the ICU LOS range was from 4.6d to 21.8d. Chemotherapy was administered in a subset of all AML hospitalizations (N=3,646; 29.1%), including 2,190 where AML was principal diagnosis. For hospitalizations where chemotherapy was the principal and AML a secondary diagnosis (N=1,357), mean payments and LOS ranged from $9,339/6.1d to $48,597/24.7d. Patients were in the ICU in only 12.6% of these hospitalizations.  CONCLUSIONS: Treatment intensity and costs are high for AML patients receiving and not receiving chemotherapy. Many hospitalizations where chemotherapy is administered do not involve ICU stays, suggesting that outpatient management following chemotherapy could be safe for some patients and reduce patient burden and hospital/payer costs.