Purpose: Survival in older adults with cancer varies given differences in functional status, comorbidities, and nutrition. Prediction of factors associated with mortality, especially in hospitalized patients, allows physicians to better inform their patients about prognosis during treatment decisions. Our objective was to analyze factors associated with survival in older adults with cancer following hospitalization. Methods: Through a retrospective cohort study, we reviewed 803 patients who were admitted to Barnes-Jewish Hospital’s Oncology Acute Care of Elders (OACE) unit from 2000 to 2008. Data collected included geriatric assessments from OACE screening questionnaires as well as demographic and medical history data from chart review. The primary end point was time from index admission to death. The Cox proportional hazard modeling was performed. Results: The median age was 72.5 years old. Geriatric syndromes and functional impairment were common. Half of the patients (50.4 %) were dependent in one or more activities of daily living (ADLs), and 74 % were dependent in at least one instrumental activity of daily living (IADLs). On multivariate analysis, the following factors were significantly associated with worse overall survival: male gender; a total score <20 on Lawton’s IADL assessment; reason for admission being cardiac, pulmonary, neurologic, inadequate pain control, or failure to thrive; cancer type being thoracic, hepatobiliary, or genitourinary; readmission within 30 days; receiving cancer treatment with palliative rather than curative intent; cognitive impairment; and discharge with hospice services. Conclusions: In older adults with cancer, certain geriatric parameters are associated with shorter survival after hospitalization. Assessment of functional status, necessity for readmission, and cognitive impairment may provide prognostic information so that oncologists and their patients make more informed, individualized decisions.