Heosimcheong Spa (Korean: 허심청) is a spa 10 km north of Dongnae District, Busan, South Korea. It is said to be the largest hot spring fed spa in Asia.

It has facilities to accommodate 3000 guests on five floors. Known to have been bathed in by kings of Silla (57 BCE – 935 CE), the spring has been developed into a 4,300 m urban complex with 4 million visits a year.

The current building was completed in 1991. Separated and largely duplicated by gender, facilities include hot, lukewarm and cool baths, fountains, saunas (including an "igloo" chilled to 0 °C), mud baths, massage, exfoliation, and exercise rooms. The spring water is alkali, emerging at 45 °C to 56 °C, and has the highest concentration of magnesium in Korea. Forty different bath types are available, depending on the season, with different medicinal herbs and fruit essences, including cherry, pepper, lavender and citrus, mixed with the water. The complex also has a nightclub, a lounge, several banquet halls, a bakery, a bar (HurShimChung Bräu) and a Japanese restaurant, and is connected to a neighboring hotel by skywalk.

• Images of the different baths

35°13′16″N 129°04′57″E / 35.22111°N 129.08250°E / 35.22111; 129.08250