The separation and quantitative determination of phytic acid (inositol hexaphosphate) and lower inositol phosphates (tri-, tetra- and penta-phosphates) was carried out using a HPLC method that included purification by anion-exchange chromatography, and analysis by ion-pair chromatography on a C18 reverse phase column. Samples of the most important legumes in the Mediterranean diet were analysed using this system. The different samples presented a variable content of phytic acid and different relative proportions of lower inositol phosphates.