The eating habits of sea vegetables (edible seaweeds) in the north Kinki coastal area were investigated by informal interview of the residents. The results were as follows : 1) 22 kinds of sea vegetables were eaten, and more kinds of brown and red algae were consumed than green algae. 2) Almost all of these sea vegetables were harvested by the residents for self-sufficient food, only wakame and mozuku were efficient sources of income. 3) The scientific properties of sea vegetables that the residents learned from their experiences were utilized in the traditional method for drying, storing and processing the sea vegetables. 4) The sea vegetables were used as daily food, substitutes for the vegetables in the winter and emergency food for the year of poor fish catch, bad crops and during the war. 5) Arame, hijiki, egonori, tengusa, and igisu have been used as food for events concerning Buddhist rituals, on the other hand, mozuku, egonori, tengusa, igisu and iwanori have been used on celebratory occasions. Concerning all of the eating habits of sea vegetables except the purpose of harvesting of sea vegetables, these features in the north Kinki coastal area resembled closely the eastern part of Sanin coastal area. The regional differences of the purpose of harvesting sea vegetables were greatly influenced by the social environment, especially the occupational form.