BACKGROUND AND OBJECTIVES: The use of opioids in cancer is already widespread and proven by several well-controlled clinical trials. However, the elderly with cancer pain are undertreated due to the lack of knowledge in the management of these patients, the underestimation of pain, as well as the fear of complications arising in this age group. Therefore, the scientific community contributes to giving inputs to create possible clinical and health guidelines. The present study aimed to perform a systematic literature review of opioid treatments proposed for cancer-related pain in elderly patients. CONTENTS: The search on the literature included papers addressing cancer pain treatment with opioids among the elderly, published from 2008 to 2018, and available in Portuguese or English. Searches were conducted on Medical Literature, Analysis, and Retrieval System Online (MEDLINE) and Latin American and Caribbean Health Sciences Literature (LILACS) electronic databases using the keywords "cancer pain", "opioids", and "elderly" in both languages, combined with the Boolean operator "AND". To analyze the quality of the method, the adapted Critical Appraisal Skills Programme was used. Of a total of 411 studies found, 32 were included. About 75% of the selected articles were published in the last five years. CONCLUSION: The results showed that opioids remain the pillar to treat cancer-related pain in the elderly. They can be used for better management of pain, but with caution due to the possible adverse effects. In addition, pain management in the elderly requires a multifactorial analysis, including comorbidities, polypharmacy, and patient functionality. Therefore, an individualized approach in the elderly patient is required in order to enhance results, reduce side effects, and improve quality of life.