Abstract: The instability, agglomeration and poor transport properties of nano zero-valent iron (nZVI) greatly limit its application in the removal of contaminants in environmental systems. To resolve these problems, many porous materials are served as a matrix to support nZVI for pollutant remediation. Metal-organic frameworks (MOFs), constructing with inorganic nodes and organic linkers through coordination bonds, are booming as fascinating porous crystalline materials. Herein, Fe-based MOFs MIL-100 (Fe) was successfully utilized as a novel precursor for carbothermal reduction synthesis of nZVI/C for effective removal of methyl orange (MO). The effect of carbothermal temperature was studied. Under the optimized carbothermal temperature (750℃), the synthesized nZVI/C had a BET area of 364 m²/g and nZVIs with an average distribution of 10 nm were uniformly distributed in the carbon matrix with high-loading and controllable particle size. As a result, the elaborated sample could rapidly remove methyl orange (MO) in the first 20 min and the removal efficiency was as high as 100% in 2 h, showing excellent MO uptake performance with the maximum adsorption amounts of 78.4 mg/g, which was also higher than that of C material. The impacts of the most significant parameters such as contact time, the initial nZVI/C concentration and pH on the removal efficiency of MO and the adsorption capacities were investigated. The removal efficiency on MO increased with nZVI/C concentration while increased pH value led to lower removal efficiency. The removal process was closed to pseudo-second-order model and Langmuir model. The regenerated nZVI/C could still preserve almost half of removal efficiency after three times reuse. Regards to the high BET area with open structure, uniform particle distribution and the relative easiness for large-scale synthesis, nZVI/C holds great potentials for MO decontamination from waste water.