Background Older cancer patients are more likely to present with functional dependency, multiple comorbidities, polypharmacy, malnutrition, and cognitive dysfunction than their younger counterparts which increases the risk of elder abuse. Herein, in this single-institution observational study, we aimed to determine the frequency and risk factors of abuse in cancer patients aged 70 and above. Methods A total of 217 cancer patients aged >= 70 years who applied to the medical oncology outpatient clinic between June 2020 and January 2021 were included in this study. Informed consent was obtained before data collection. The Hwalek-Sengstock Elder Abuse Screening Test (H-S/EAST) was used to evaluate elder abuse. Sociodemographic characteristics and clinical measurements were collected. Results The mean age was 75.5, and 59.4% were male. The prevalence of abuse risk in older patients with cancer was 39.2%. In the multivariate logistic regression model, applying to the outpatient clinic for treatment (OR: 3.369, 95% CI: 1.455-7.802, p = 0.005), living in urban (OR: 5.787, 95% CI: 2.377-14.090, p < 0.001), history of falls (OR: 4.587, 95% CI: 1.789-11.762, p = 0.002), and being depressed according to the Geriatric Depression Scale-15 (GDS-15) score (OR: 10.788, 95% CI: 4.491-25.914, p < 0.001) were associated with an increased risk of elder abuse. Primary/junior education level and high school/university education level were protective against elder abuse risk compared to being illiterate (OR: 0.073, 95% CI: 0.025-0.210 and OR: 0.213, 95% CI: 0.056-0.806, respectively). Conclusion Cancer patients aged >= 70 years had a high risk of elder abuse. Elder abuse should be screened in patients with cancer, and the effects of this phenomenon on cancer care should be investigated in larger studies.