Simultaneous analysis was examined for eight types of preservatives, benzoic acid, sorbic acid, dehydroacetic acid, ethyl p-hydroxybenzoate, isopropyl p-hydroxybenzoate, propyl p-hydroxybenzoate, isobutyl p-hydroxybenzoate and butyl p-hydroxybenzoate, in foods by liquid chromatography after solvent extraction and solid-phase purification. Recovery tests using four types of food showed good results with recovery rates of 92 to 110%, repeatability RSD of 1.2 to 7.0%, and laboratory reproducibility RSD of 2.6 to 9.5%.