In this study, a nanocomposite catalyst was prepared by combining Fe@Fe2O3 core−shell nanowires and carbon nanotubes (CNTs) with poly(tetrafluoroethylene) suspension (Fe@Fe2O3/CNTs/PTFE). The resulting Fe@Fe2O3/CNTs/PTFE catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and Fourier transform infrared (FT-IR) analysis. The microwave-induced catalytic oxidation (MICO) of rhodamine B with the Fe@Fe2O3/CNTs/PTFE catalyst was investigated. The degradation efficiency of rhodamine B (5 mg L−1) reached 100% within 6 min under microwave irradiation in the presence of the composite catalyst. Moreover, it was found that the Fe@Fe2O3/CNTs/PTFE catalyst could be recycled without the obvious loss of catalytic ability. On the basis of characterization results, a possible mechanism of microwave-induced catalytic oxidation of RhB with the Fe@Fe2O3/CNTs/PTFE catalyst was proposed. The high catalytic activity of the Fe@Fe2O3/CNTs/PTFE catalyst and its mass production make it a promising technology for wastewater treatment