Carbon-based magnetic nanostructures in several instances have resulted in improved physicochemical and catalytic properties when compared to multi-wall carbon nanotubes (MWCNTs) and magnetic nanoparticles. In this study, magnetic MWCNTs with a structure of NixZnxFe2O4/MWCNT as peroxidase mimics were fabricated by the one-pot hydrothermal method. The structure, composition and morphology of the nanocomposites were characterized with X-ray diffraction (XRD), Fourier transform infrared spectroscopy and transmission electron microscopy. The magnetic properties were investigated with a vibrating sample magnetometer. The peroxidase-like catalytic activity of the nanocomposites was investigated by colorimetric and electrochemical tests with 3,3´,5,5´-tetramethylbenzidine (TMB) and H2O2 as the substrates. The results show that the synthesis of the nanocomposites was successfully performed. XRD analysis confirmed the crystalline structures of the NixZnxFe2O4/ MWCNT nanohybrids and MWCNTs. The main peaks of the NixZnxFe2O4/MWCNTs crystals were presented. The Ni0.25Zn0.25Fe2O4/MWCNT and Ni0.5Zn0.5Fe2O4/MWCNT nanocatalysts showed nearly similar physicochemical properties, but the Ni0.5Zn0.5Fe2O4/MWCNT nanocatalyst was more appropriate than the Ni0.25Zn0.25Fe2O4/MWCNT nanocatalyst in terms of the magnetic properties and catalytic activity. The optimum peroxidase-like activity of the nanocatalysts was obtained at pH 3.0. The Ni0.5Zn0.5Fe2O4/MWCNT nanocatalyst exhibited a good peroxidase-like activity. These magnetic nanocatalysts can be suitable candidates for future enzyme-based applications such as the detection of glucose and H2O2.