In this work, metal-organic frameworks (MOFs) Fe-MIL-101 was synthesized by hydrothermal method, and Fe/Fe-MIL-101 with different loadings was prepared. The crystal structure of the Fe/Fe-MIL-101 sample was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and specific surface area measurement (BET). Fe/Fe-MIL-101 was found to posses an intrinsic enzyme mimicking activity similar to that found in natural horse-radish peroxidase (HRP). The Michaelis constant (K_m) of 5% Fe/Fe-MIL-101 with ABTS as the substrate is about 10-fold smaller than Fe-MIL-101 and about 3-fold smaller than HRP, and about 108 times less than that of CuO NPs (K_m = 10.28 mM), indicating a much higher affinity for ABTS than HRP and most of the peroxidase mimetics.