Chemotherapy causes various side effects, including cognitive impairment, known as 'chemobrain'. In this study, we determined whether a novel acupuncture mode called electroacupuncture trigeminal nerve stimulation plus body acupuncture (EA/TNS + BA) could produce better outcomes than minimum acupuncture stimulation (MAS) as controls in treating chemobrain and other symptoms in breast cancer patients. In this assessor- and participant-blinded, randomized controlled trial, 93 breast cancer patients under or post chemotherapy were randomly assigned to EA/TNS + BA (n = 46) and MAS (n = 47) for 2 sessions per week over 8 weeks. The Montreal Cognitive Assessment (MoCA) served as the primary outcome. Digit span test was the secondary outcomes for attentional function and working memory. The quality of life and multiple functional assessments were also evaluated. EA/TNS + BA treated group had much better performance than MAS-treated group on reverse digit span test at Week 2 and Week 8, with medium effect sizes of 0.53 and 0.48, respectively, although no significant differences were observed in MoCA score and prevalence of chemobrain between the two groups. EA/TNS + BA also markedly reduced incidences of diarrhoea, poor appetite, headache, anxiety, and irritation, and improved social/family and emotional wellbeing compared to MAS. These results suggest that EA/TNS + BA may have particular benefits in reducing chemotherapy-induced working memory impairment and the incidence of certain digestive, neurological, and distress-related symptoms. It could serve as an effective intervention for breast cancer patients under and post chemotherapy (trial registration: https://www.clinicaltrials.gov: NCT02457039). Copyright © 2020 Elsevier Inc. All rights reserved.