Derivatives of C-60/C-70 fullerene and multi-walled carbon nanotubes (MWCNTs) with piperidine fragments were synthesized and their antioxidative activity was determined. The antioxidant activity of the investigated derivatives was studied by measuring the inhibition rate constants for their reaction with peroxy radicals in a model cumene initiated oxidation experiments and compared with that for commercial primary aromatic amine stabilizers. The inhibition rate constants for trapping of peroxy radicals by the MWCNTs amine derivatives were found to be higher than that of known aromatic amine antioxidants Neozone-D and Naugard 445. These novel compounds may be considered as promising broad-spectrum radical scavenging antioxidants.