To obtain high purity esters of a sterol and a stannole in a good yield on a large scale, which enable them to be processed in a food grade without the existence of both any organic solvent and any inorganic acid by directly esterifying a stannole and/or a sterol in the presence of a weakly acidic catalyst to separate their esters.

(D) stannole and/or sterol esters of formula III [R1 is a (ca. 6-25)C carbon chain] are obtained by reacting (A) a stannole and/or a sterol each expressed by formula I (R2 is a 3-15C carbon chain), e.g. a stannole and/or a sterol of formula II with (B) an acid in the presence of (C) a weakly acidic catalyst. For example, when reacting β-cytostannole with stearic acid to form a β-cytostannole stearate, the β-cytostannole stearate is converted into a stigmastannole stearate in the presence of NaHSO4 and is isolated. The resultant ester is expected to be useful for the reduction of serum cholesterol.