Iron deficiency anemia (IDA) is a prevalent nutritional deficiency problem. This study aimed to investigate the characteristics of Choerospondias axillaris polysaccharide-Fe (III) complex and its effect on IDA mice. CAP-Fe (III) complex was synthesized by co-thermal synthesis method with an iron content of 27.31 +/- 0.97 %. The chelation of Fe3+ reduced the crystallinity, increased the thermal stability and changed the morphological features of CAP, which was evidenced by XRD, TG, and SEM analysis. The probable existence of the beta-FeOOH structure was supported by the characteristic absorption peaks in the FT-IR, XRD, and Mo<spacing diaeresis>ssbauer spectra. The CAP-Fe (III) complex showed a therapeutic effect on IDA mice, confirmed by improved erythroid parameters, iron levels, and oxidative stress. The results of gene expression levels determined by RT-qPCR demonstrated that the CAP-Fe (III) complex could regulate iron metabolism homeostasis, alleviate liver inflammation, and enhance intestinal barrier function. Furthermore, the dysbiosis of intestinal microbiota induced by IDA was effectively restored by CAPFe (III) complex, through enriching beneficial bacteria (Firmicutes, Blautia, Oscillibacter, Colidextribacter) and depleting harmful bacteria (Actinobacteria, Proteobacteria, Parasutterella, Faecalibaculum, Escherichia-Shigella). These findings suggested that CAP-Fe (III) may serve as a novel iron supplement for treating IDA.