We have developed a determination method for alcohol using high-performance liquid chromatography by using a diamond electrode-electrochemical detector. At this time, 4 alcohols (methanol, ethanol, 2-propanol and 1-butanol) were separated on a Shodex® ODP2 HP-4E column with an acetonitrile-25 mM disodium hydrogen phosphate buffer (pH 11.0, 1 : 99, v/v) as the mobile phase. The electrochemical detector, equipped with a diamond electrode, was set at 2000 mV (applied voltage). The detection limits of the four alcohols were 20-25 ng/mL. The proposed liquid chromatography was fifty-times more sensitive compared to reported gas chromatography – flame ionization method, and was found to be suitable for large-volume aqueous sample solutions compared to gas chromatography. In the case of poor absorbance compounds, an easy-to-set additional detector in wide using the liquid chromatography – ultraviolet detection system. It was meaningful economical work to use an existing apparatus in the laboratory. With this method, one could determine volatile alcohols, e.g., ethanol, which could not be determined by other universal-type detectors (corona-CAD and ELSD). The proposed method was applied to the alcohol in detergents (contains ethanol and 2-propanol) and alcoholic beverages. Good relationships were obtained compared to the enzymatic method.