In this study, the proximate composition of Pyropia dentata was compared by the analysis of minerals and amino acids that were produced at Seocheon, Chungcheongnam-do and at Wando and Jangheung, Jeollanam-do. Moisture, ash and crude proteins were analyzed using the AOAC method, and crude lipid was analyzed using the Soxhlet method, and inorganic analysis was performed using ICP-OES. Amino acid was used for the amino acid analyzer. The proximate composition analysis, moisture content, maximum values were displayed in Wando while the maximum content of ash appeared at Jangheung's Pyropia. Crude proteins was appeared at Seocheon's Pyropia and the maximum amount of crude lipid, carbohydrate was appeared in Wando's Pyropia. Inorganic analysis, calcium, potassium, magnesium, sodium, phosphorus, cobalt, chromium, copper, iron, manganese, nickel, zinc were analyzed from the Seocheon's Pyropia, however, cobalt, chromium, and nickel was not detected in Wando's Pyropia. For amino acid analysis, a total of 17 amino acids were detected: leucine, valine, aspartic acid, glutamic acid, and the amount of alanine accounted for about 57 % of total amino acids(26.1-28.7 %). The proximate composition, minerals, and amino acid of Pyropia dentata were different depending on the coastal ecological habitats.