Nanocrystalline LaFeO3 was synthesised by the citrate method with La(NO3)3·6H2O,Fe(NO3)3·9H2O and citric acid as the raw materials. Before and after reduction, its structure was characterized by means of X ray diffraction and transmission electron microscopy(TEM). And after reduction of LaFeO3 oxide, the rareearth oxide, La2O3, prevents Fe particles from agglomerating and promotes the dispersion of nano scale Fe particles (ca.40nm), which is one of the key factors for the growth of carbon nanotube. The carbon nanotubes from the catalytic decomposition of C2H2 were obtained using Fe/La2O3 nano scale catalyst, which wasformed from LaFeO3 oxide as the catalyst precursor. The morphological structures of the carbon nanotube obtained have been examined by TEM. The results indicate that they are multi walled nanotubes of good quality with inter diameter ranging from 20～25nm and length ranging from 25～40μm. The yields of carbon nanotube are 1.25g·gcat-1 at the reaction temperature of 973K for 30min.
