The diethylisopropylsilyl (DEIPS) group which is a new protective group for alcohols has been first characterized. DEIPS group can be distinguished from t-butyldimethylsilyl, triethylsilyl, tetrahydropyranyl groups and 2-deoxy glycoside with high selectivity in removing under mild acidic condition, although DEIPS group has high stability to many useful organic synthetic reaction conditions.