A technique for admicelle-based solid phase extraction is presented in which a dialkylammonium surfactant in the hydroxide form is immobilized on silica. By converting dihexadecyldimethylammonium bromide to the hydroxide form, the surfactant is allowed to have the property of a strong base, aiding in the extraction of acidic phenols which are difficult to extract because of their differing polarities. The surfactant-silica admicelle parameters were optimized for the efficient extraction of eight phenols. Adsorbed phenols were eluted from the sorbent using small volumes of methanol. The phenols were preconcentrated from drinking water samples and were determined using high performance liquid chromatography (HPLC) coupled with a photo diode-array detector.