Imun Seolnongtang (Korean: 이문설농탕; Hanja: 里門雪濃湯) is a historic restaurant in Seoul, South Korea.

[2][5] After an investigation, in 2011, the Seoul Metropolitan Government gave the founding year as 1904, and affirmed that it was the oldest restaurant.

[6] During the colonial period, a man named Hong Jong-hwan (홍종환; 洪鍾煥) has been attested to being an owner of the restaurant.

[6][2] During the colonial period, the restaurant was reportedly seen as a premiere location for seolleongtang, and the dish was seen as the representative food of Seoul (then Keijō).

A number of South Korean athletes frequented the restaurant, including boxers Moon Sung-kil and Kim Kwang-sun and judoka Ha Hyung-joo.

[2][6] Some athletes who visited it were reportedly so devoted to the restaurant that they jokingly founded a "Imun Society" (이문회).