We aimed to examine the effects of an individualised multicomponent exercise program on functional outcomes in hospitalized older patients with cancer. Patients aged ≥ 65 were recruited upon admission to a Medical Oncology Department and randomly allocated to receive a multicomponent exercise training program twice daily for five days or standard hospital care. The primary outcome measure was the change in functional status using the Short Physical Performance Battery. This study allocated 30 patients in the Control group and 28 in the intervention group. The mean age was 74.4 years. The intervention group (n = 14) showed significant improvements vs the Control group (n = 20) in the Short Physical Performance Battery (SPPB) (between-group difference, 1.92; 95% CI = 0.80,3.07), knee extension strength (between-group difference 7.72; 95% CI = 1.83,13.8), as well as a significant reduction in fatigue (between-group difference -26.5; 95% CI=-38.6,-13.9). This individualized exercise program appears to have contributed to improving functional abilities and reducing fatigue in hospitalized older cancer patients.