Memil guksu is a traditional South Korean soba noodle soup, hence the name, with memil meaning buckwheat, and guksu meaning noodle soup. The dish consists of buckwheat noodles, eggs, green onions, and seaweed. They're boiled in a broth made from guksijangguk and Japanese hondashi.

Once cooked, the noodles are topped with the eggs and toasted seaweed strips. The dish can be enriched with lemon juice, and it's sometimes served with a dipping sauce based on tsuyu and rice wine on the side. Memil guksu noodles are always served cold.