The extraction rates of minerals from Suboshi-, Haiboshi- and Enzo-Wakame (Undaria pinnatifida) into immersion water were determined. Ninety percent of iodine was extracted into water during a 10 min immersion in the cases of Suboshi-Wakame and Haiboshi-Wakame but only 34% in the case of Enzo-Wakame. There were no great differences among the Wakame in extraction rates of minerals except iodine: the rates were 60-70% for sodium, 40-70% for potassium, 20-60% for phosphorus, 2-20% for calcium and 6-40% for magnesium. Haiboshi-Wakame showed the lowest rate of mineral extraction among the three kinds of processed Wakame. The extraction rates of minerals in Wakame seemed to be related with processing treatments such as blanching, washing and ash-sprinkling.