A high yield synthesis for lanthanofullerenes has been studied by a newly developed fullerene arc generator equipped with ananaerobic sampling apparatus. The yield of the lanthanofullerene La @ C82 has increased by a factor of 10 or more, when LaC2-enriched composite carbon rods are used for the generation of soot, instead of hydrooxidized or oxidized lanthanum composite rods. The fact is characterized by electron spin resonance and by the powder X-ray diffraction method. Furthermore, the yields of other types of lanthanofullerenes, LaC2n, have also increased, when the LaC2-enriched composite rod is used as an arc-burning material.