The literature about the factors associated with cancer treatment refusal, especially by the older patients is scarce. Therefore, this study aimed to identify predictive factors associated with treatment refusal by older patients with cancer. A systematic review was conducted using three databases, Medline, Web of Science, and Scopus with the key concepts, "refusal treatment" and "cancer" and "decision making" and "elderly" or "aged". The search took place in July 2020 and it included articles published in the last 5 years.Of the 211 articles found, 22 were included in the review. Most studies have focused on head and neck and breast cancer treatment decisions and used a quantitative design. The majority of studies evaluated refusal of surgery interventions. Important factors associated with refusal cancer treatment include gender, marital status, race, having government insurance, advanced cancer, poor performance status (cancer stage III or IV) and Charlson Comorbidity Index ≥2. Thus, there are socio-demographic and clinical variables associated with treatment refusal. More studies with the elderly are needed. Understanding these factors may be useful to recognize situations where active education and support can help elderly patients accept optimal care.