Sansui County is located in the east of Guizhou Province, under the Qiandongnan Miao and Dong Autonomous Prefecture. Located between 108°32 '-109°04' east longitude and 26°47 '-27°04' north latitude, it is adjacent to Xinhuang Dong Autonomous County of Hunan Province in the northeast, bordering Tianzhu and Jianhe counties in the southeast and southwest, and connected to Zhenyuan County in the north. As one of the east exports of Guizhou Province, it is known as the "stronghold of East Guizhou" and the "gateway of Qianli Miao". The county has jurisdiction over 7 towns and 2 townships, 159 villages and 5 residential communities, with a total area of 1035 square kilometers. County people's government in Bagong, 87 kilometers away from the state capital Kaili, 247 kilometers away from the provincial capital Guiyang. According to the seventh census, as of midnight on November 1, 2020, the permanent population of Sansui County was 162,798.

Sansui has superior natural endowments and is named "Hometown of Chinese Folk Bamboo Weaving Art" by the Ministry of Culture. In 1972, the Wazhai bamboo hat was presented as a state gift to the visiting US President Richard Nixon. In 2007, Sansui bamboo knitting was listed as an intangible cultural heritage of Guizhou Province. In 2008, the Ministry of Culture named Sansui the "Hometown of Chinese Folk Culture and Art (Bamboo Weaving)". Known as the "hometown of hemp duck" and "Hometown of bamboo hats", it is the source of Sansui duck, a local famous duck in China.

On September 25, 2018, it was awarded the honorary title of "2018 E-commerce into Rural Comprehensive Demonstration County" by the Ministry of Commerce.

On February 2, 2019, it was named as the advanced unit of grassroots TCM work at the county level by the State Administration of Traditional Chinese Medicine. On April 24, 2019, Guizhou Provincial People's Government officially approved Sansui County's withdrawal from the poverty-stricken county list. In 2020, the GDP of Sansui County was 511499 million yuan, an increase of 6.8% over the previous year (hereinafter referred to as "growth").