A catalyst, ferroferric oxide nanoparticles decorated with multiwalled carbon nanotubes was successfully fabricated, and applied for the degradation of norfloxacin in the presence of H2O2 and xenon light. The catalyst was characterized by different techniques i.e., X-ray diffraction, transmission electron microscope, and fourier transform infrared. The effects of initial pH, catalyst dosage, hydrogen peroxide concentration and iron leaching on the degradation of norfloxacin were studied. The multiwalled carbon nanotubes showed higher ability of degradation efficiency of norfloxacin than bare Fe3O4 nanoparticles in the batch degradation experiment. The results showed that the multiwalled carbon nanotubes catalyst demonstrated good performance in the degradation of norfloxacin with optimum operating conditions of multiwalled carbon nanotubes 1.2 g L-1, pH 3.0, H2O2 0.098 mol L-1 and the multiwalled carbon nanotubes catalyst still exhibited good chemical stability after five consecutive degradation cycles. Further, the catalyst showed stable catalytic activity, fairly good mechanic stability and convenient recycling. Negligible iron leaching demonstrated the reused multiwalled carbon nanotubes could withstood the oxidation.