In this research, a novel multiwall carbon nanotube/polyaniline (PANI–MWCNTs)-based metal oxides nanocomplex as a peroxidase mimetic was fabricated and characterized. Finally the peroxidase-like catalytic activity of nanocatalyst was investigated with the oxidation of peroxidase substrates: 4-aminoantipyrine (4-AAP)/phenol system and 3,3′,5,5′-tetramethylbenzidine (TMB) substrate in the presence of H₂O₂ reagent.