In this study, recent literatures and clinical research experience were collected and analyzed. The main problems of acupuncture in the treatment of cancer pains were summarized and listed as follows. (1) Cancer pains have complex causes and diverse symptoms, and some mixed pains need other drugs for adjuvant treatment. (2) Limited degree of pain control. For mild to moderate pains (pains with a numerical rating scale [NRS] score of <4 points), good results can be achieved; while for severe pains (pains with an NRS score of ≥ 4 points), drug treatment must be concurrently performed. (3) Analgesia timeliness. After treatment, the majority of patients felt that their pains gradually aggravated. Hence, these patients were returned to pre-treatment level at 4-6 h after treatment. (4) Diverse selection of acupoints. In China, most researchers use the TEAS method, where they select acupoints based on syndrome differentiation; and researchers sometimes use local acupoint selection as adjuvant means. Most foreign researchers treat cancer pain using the TENS method. (5) It is difficult to conduct randomized double-blind controlled studies of this treatment. Because, the treatment of acupuncture is easier to be identified by patients with acupuncture or electro-acupuncture experience.