Aims: To analyze the scientific evidence available in the literature about the effect of auricular acupuncture on cancer pain. Method: Systematic review of the literature guided by the criteria of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA Statement); whose research question was “What are the effects of auriculotherapy/auricular acupuncture on cancer pain in adults?”. EndNote and Rayyan platforms were used to manage references and manage the stages of article selection, respectively. The Jadad scale was used to assess the methodological quality of the studies. The data collected from the articles were grouped into tables and analyzed descriptively. Results: A total of 3484 articles were found, of which 11 made up the sample of this study, in which the majority showed excellent methodological quality (54.54%). 533 adults complaining of cancer pain were treated, using auricular acupuncture as the only intervention or as a complement to another treatment and, in all studies, it proved to be effective both for painful symptoms and for relieving other secondary signs, such as anxiety and insomnia. Conclusions: Auricular acupuncture is effective in relieving cancer pain when administered either through needles or seeds and at specific pain points (aché point), in addition to the shemman, sympathetic, subcortex, and kidney points.