We describe the growth of amorphous carbon nanofibers (CNFs) from iron-encapsulated dendrimer catalysts at ambient temperature and pressure conditions. Both fourth-generation poly (propyleneimine) (PPI) and poly(amidoamine) (PAMAM) dendrimers were suitable macromolecular hosts for the catalytic species. Average nanofiber diameters range from 10 - 15 nm, with lengths in excess of 20 microns.