The physiological activities and amino acid compositions of dried layers of Porphyra from the Jangheung, Seochen and Haenam coasts were determined, The ethanol extract of the Haenam dried layer exhibited the greatest I , 1 -diphenyl2-picryihydrazyl (DPPH) radical scavenging activity (56.1%), ferric-reducing antioxidant potential (FRAP) value(86.5mM) and total polyphenol content (3.51 ppm) of these dried layer products. In addition, there was a strong positive correlation between the antioxidative activity and total polyphenol content of the layer products, suggesting that polyphenol compounds contribute to the antioxidant capacity in the ethanol extract of dried layer. However, there was no difference among the extracts in terms of cell proliferation activity. Fourteen combined amino acids were identified in oligopeptides from the dried layer products. Of the three extracts, that of the Haenam dried layer contained the highest levels of both free and total amino acids including alanine, glutamic acid, taurine, phosphoserine, and aspartic acid.