Iron-copper bimetallic nanoparticles supported on carbon nanofibers as a composite catalyst (FeCu/CNF) was prepared for the first time in this work. The iron-copper bimetallic nanoparticles were formed in situ by carbothermic reduction during the carbonization process. The characterization results show that the FeCu/CNF possesses fibrous morphology, porous structure with high specific surface area, and dispersed iron-copper nanoparticles. For comparison, three other catalysts, including solely iron nanoparticles supported on carbon nanofibers (Fe/CNF), solely copper nanoparticles supported on carbon nanofibers (Cu/CNF) and iron-copper nanoparticles supported on blocky carbon matrixes (FeCu/C) were also prepared. The heterogeneous Fenton catalytic performance of synthesized catalyst was evaluated by degradating a typical azo dye, Acid Orange II (AOII). The results show that almost 97.7% of 100 mg/L AOII is removed by FeCu/CNF in reaction time of 1 h, which is much higher than those of comparison catalysts operated in the same experimental condition. Additionally, the FeCu/CNF also reveals a Wider pH adaptation ability compared with Fe/CNF. Based on the results of center dot OH detection and resistance of mass transfer testing in catalysts, the remarkable catalytic performance of FeCu/CNF is considered as the synergistic effect of iron and copper and the superiority of nanofibrous structure in catalyst. The good stability and recoverability of FeCu/CNF were also demonstrated. The as-synthesized catalyst is proved to be an attractive candidate in heterogeneous Fenton chemistry. (C) 2017 Elsevier B.V. All rights reserved.