Some typical multi-valent metal salts, such as chloride, nitrate, sulfate, and acetate of Fe(III), Al(III), Ga(III), In(III), Zr(IV), HF(IV), Zn(II), Co(II), Ni(II), Mn(III), Cr(III), and Cu(II) have catalytic acitivties for the esterification of saturated and unsaturated long chain aliphatic acids with long chain aliphatic alcohols. These catalysts were sponteneously separated from the reaction mixtures, and could be subjected to the recycle use for the further reactions.