Abstract: Colon cancer-related anemia (CCRA) is mainly caused by systemic inflammation, intestinal bleeding, iron deficiency and chemotherapy-induced myelosuppression in colon cancer. However, the best therapeutic schedule and related mechanism on CCRA were still uncertain. Studies on blood enrichment and anti-tumor effects of combined Danggui Buxue Decoction (DBD), Fe and rhEPO based on CCRA and gut microbiota modulation were conducted in this paper. Here, CCRA model was successfully induced by subcutaneous inoculation of CT-26 and i.p. oxaliplatin, rhEPO + DBD high dosage + Fe (EDF) and rhEPO + DBD high dosage (ED) groups had the best blood enrichment effect. Attractively, EDF group also showed antitumor activity. The sequencing results of gut microbiota showed that compared to P group, the relative abundances of Lachnospiraceae and opportunistic pathogen (Odoribacter) in ED and EDF groups were decreased. Interestingly, EDF also decreased the relative abundances of cancer-related bacteria (Helicobacter, Lactococcus, Alloprevotella) and imbalance-inducing bacteria (Escherichia-Shigella and Parabacteroides) and increased the relative abundances of butyrate-producing bacteria (Ruminococcaceae_UCG-014), however, ED showed the opposite effects to EDF, this might be the reason of the smaller tumor volume in EDF group. Our findings proposed the best treatment combination of DBD, rhEPO and Fe in CCRA and provided theoretical basis and literature reference for CCRA-induced intestinal flora disorder and the regulatory mechanism of EDF.