gamma-Fe2O3-impregnated magnetic carbon nanotubes (CNTs) have been fabricated by the carbonization of polypyrrole (PPy) nanotubes. It is found that PPy nanotubes form graphitic structures at a low temperature (800degreesC). Magnetic CNTs (see Figure) show ferromagnetic behavior even at 300 K and the main magnetic phase of the CNTs is gamma-Fe2O3. This novel fabrication approach is expected to provide an alternative way to fabricate CNTs.