PURPOSE: A manufacturing method of soy sauce containing seaweed extract is provided to offer environmental friendly effects in the soy sauce without adding a chemical additive, and to improve nutrients with fish sauce and seaweed. CONSTITUTION: A manufacturing method of soy sauce containing seaweed extract comprises the following steps: drying Ecklonia cava and Laminaria japonica with sea wind in the shade; making concentrate by boiling the collected materials with water for 2 ~ 3 hours; adjusting salinity of concentrate by adding bay salt 20 ~ 23 weight%; manufacturing Ecklonia cava and Laminaria japonica concentrate by aging the concentrate for 6 months; making liquid salted fish through a filtering and concentrating processes; manufacturing concentrate of Scomber japonicas or Trachurus japonicas; drying dried radish slices or carrots to make concentrate; making the concentrate of the dried radish slices or the carrots; mixing each concentrate; and sterilizing the mixed concentrate at a temperature of 90 ~
