We have developed a single-step method for selectively extracting endohedral metallofullerenes. In this new method, a mixed solvent of triethylamine and acetone is used to extract endohedral metallofullerenes from raw soot. The efficiency of extraction was investigated by extracting Ce-containing metallofullerenes, Ce@C-82 and Ce-2@C-80, from raw soot obtained by an arc discharge technique. The resultant extract contained little or no empty fullerenes such as C-60 or C-70, that is, the Ce-metallofullerenes were selectively extracted.