Objective Fatigue is the most common side effect in cancer and cancer treatment. This study aimed to investigate the effect of different amounts of exercise on fatigue in patients with digestive tumors. Methods We searched articles published to March 2024 in the PubMed, Embase, Web of Science, and Cochrane databases. The amount of exercise was evaluated according to the American College of Sports Medicine (ACSM) and divided into high compliance and low compliance. The effect of compliance on fatigue in patients with digestive tumors was compared using standardized mean difference and 95% confidence intervals (95% CI). Results A total of 18 articles were included, and we found that exercise had beneficial effects on cancer-related fatigue (CRF) in patients with digestive tumors. Fifteen studies that met the ACSM recommendations were grouped eventually. Eight studies were classified as high compliance and 7 studies as low compliance. The CRF was improved significantly in the high compliance (- 1.89; 95% [CI], - 2.93 to - 0.86) compared with the low compliance (- 1.43; 95% [CI], - 2.25 to - 0.61). Conclusion Exercise intervention with high compliance showed a more significant improvement in fatigue in patients with digestive tumors compared with low compliance. However, these studies have not yet been fully uniform for the scoring tool for CRF, and further studies are needed to validate these findings. Implications for Cancer Survivors Compared with low compliance, exercise intervention with high compliance has shown a more significant improvement in fatigue among patients with digestive tumors. In addition, the beneficial effects of high compliance with exercise intervention on fatigue in patients with digestive tumors also provide important implications for cancer survivors. Regular exercise that conforms to the American College of Sports Medicine (ACSM) recommendations, especially maintaining high compliance, can serve as an effective strategy to alleviate cancer-related fatigue and improve the quality of life of survivors. However, these studies have not yet been fully unified in the scoring tools for cancer-related fatigue (CRF), and further research is needed to validate these findings.