This systematic review evaluated evidence quality for exercise intervention in patients with cancer-related fatigue(CRF) during chemoradiotherapy to provide evidence-based clinical guidance. CRF is one of the most common symptoms in patients undergoing chemoradiotherapy. There is mounting evidence suggests exercise can relieve CRF and clinical practice guidelines for its management have been published in several countries. However, more specific exercise programs need to be extracted to guide the clinical practice. The review was presented by PRISMA guidelines. Research questions and strategies were established using evidence-based nursing criteria. 11 websites and databases were searched. Appraisal of Guidelines for Research and Evaluation II, the JBI literature quality assessment tool, and the JBI evidence pre-classification and evidence recommendation level system were used. 13 systematic reviews, 4 guidelines, and 1 evidence summary were included. The overall guideline quality score was 5.71, indicating high quality, with the following average scores on the six dimensions: scope and purpose, 86.81%; stakeholder group, 71.53%; rigor of the writing, 76.56%; clarity of presentation, 88.19%; applicability, 68.23%; and independence, 72.92%. We summarized 18 pieces of evidence including screening and assessment of CRF and exercise risk, health education, sports program, sports protection, and termination index. There were 12, 1, 1, and 4 pieces of evidence in grades I, II, III, and IV, respectively. The evidence recommendation was strong for 15 and weak for 3 articles. Although a normal adult exercise intensity level is considered safe for patients during chemoradiotherapy, our synthesis suggests that 18 pieces of evidence shall be followed. Future research should focus on more cancer types and more targeted exercise program design. CRF status and exercise risk should be screened and evaluated throughout exercise interventions. Interventions should be individualized, initiated at a low intensity and duration, and increased progressively.