This paper describes a simple strategy for covalently attaching nanoparticles onto the carbon nanotubes (CNTs) to fabricate hybrid nanostructure. Densely distributed magnetite nanoparticles (MNPs) with a size of similar to 8 nm have been deposited on the surface of carbon nanotubes by covalent interaction. Transmission electron microscopy (TEM), FT-IR spectroscopy, and X-ray diffraction (XRD) analysis have been used to study the formation of MNP/CNT nanostructure. The strategy employed herein is quite generic and applicable to a variety of nanoparticles, including metal, quantum dot and oxide. These composite nanostructures should open up new possibilities in areas such as nanoelectronics, chemical sensing, field-emission displays, nanotribology, and cell adhesion/biorecognition investigations. (C) 2008 Elsevier B.V. All rights reserved.