Objective <p>This study aimed to evaluate the efficacy of thunder‑fire moxibustion (TFM) for cancer‑related fatigue (CRF) in patients with Qi stagnation and blood stasis syndrome undergoing chemotherapy for colorectal cancer.</p> Methods <p>In this randomized controlled trial, 77 patients with colorectal cancer undergoing chemotherapy were randomly assigned to either a control group (conventional care) or an experimental group (conventional care plus thunder-fire moxibustion, TFM). Both groups received two treatment courses, with five intervention sessions per course. The primary outcome was the change in Revised Piper Fatigue Scale (RPFS) scores. Secondary outcomes included sleep quality assessed by the Pittsburgh Sleep Quality Index (PSQI), quality of life measured using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30), Traditional Chinese Medicine (TCM) syndrome scores, routine blood indicators, and inflammatory factor levels.Assessments were conducted before and after two intervention cycles and during a follow-up period.</p> Results Conclusion <p>Thunder‑fire moxibustion may be an effective supportive intervention for reducing fatigue and improving sleep and quality of life in patients with colorectal cancer undergoing chemotherapy.</p> Trial registration <p>This study was registered on February 11, 2025, at the International Traditional Medicine Clinical Trial Registry (Registration Number: ITMCTR2025000305).</p>