We developed a self-directed Leg And Walking Self-exercise (LAWS) program informed by the Exercise is Medicine initiative and evaluated the feasibility and acceptability of this program in older adults with cancer. Over a 1-year period, we prospectively enrolled 40 older adults who received a comprehensive geriatric assessment (CGA) at a geriatric oncology service and initiated a new line of systemic therapy for advanced cancer as inpatients. LAWS is a tailored, self-directed exercise program consisting of leg resistance training and walking. Exercise adherence was recorded using an exercise diary to assess feasibility. Patient perspectives on this program were evaluated using the Feasibility of Intervention Measure (FIM) and Acceptability of Intervention Measure (AIM), with a score range of 1-5, higher being better. Overall, 28% of patients were fit, 53% pre-frail, and 20% frail based on the CGA. During hospitalization (average 12days), 63% of the patients adhered to exercises at lowest intensity during more than 50% of their inpatient stay: on average, 2.8 leg exercises, 23 repetitions a day, 5.6days/week, and 19min of walking a day, 4.9days/week. Patients rated their perceived exertion at 3.0 for leg exercise and 3.0 for walking on a 1-10 Likert scale. During the period between discharge and their first outpatient appointment (average 11days), 71% of patients adhered to the LAWS program. Mean scores of FIM and AIM were 4.2 (SD = 0.5) and 4.2 (SD = 0.7), respectively. For older adults undergoing cancer treatment, LAWS is a feasible and acceptable self-directed exercise program.