Osai Sushi Jamsil is an omakase sushi restaurant in Jamsil, Seoul, located on the basement floor of the Samsung Life Building on Olympic-ro in Songpa-gu. It serves a lunch course and a ten-piece sushi set, with each ordered piece of sushi pressed and handed over one at a time. The restaurant is run by a cooperative, and meals are served according to the reserved time. There is only counter seating and no rooms.