Longxi County, under the jurisdiction of Dingxi City, Gansu Province, is located in the southeast of Gansu Province, the middle of Dingxi City, the upper reaches of the Weihe River, and the middle of the Loess Plateau in the middle of Gansu Province. It is adjacent to Tongwei County in the east, Wushan County and Zhangxian County in the south, Weiyuan County in the west and Anding District in the north. Longxi, named after its location in the west of Longshan Mountain, has been a "country of four fortresses" since ancient times and a place that military strategists must contend for. As far back as prehistoric times, ancestors lived and multiplied on this land, leaving Yangshao, Qijia and other cultural sites. Longxi County was established in the 35th year of King Zhao of Qin Dynasty (272 BC), and Xiangwu County was established in the early Han Dynasty. Longxi County was changed in Sui Dynasty, and the name of the county has still been used. According to the data of the seventh population census, as of 0:00 on November 1, 2020, there are 427373 permanent residents in Longxi County.

By 2020, it has jurisdiction over 12 towns, 5 townships, 215 villages and 11 communities, with a total area of 2408 square kilometers. Most of the local people in Longxi use the Central Plains Mandarin - Qinlong dialect.

Agriculture takes traditional Chinese medicine, potatoes, mushrooms and vegetables, livestock and grass as its main industries; The industry is dominated by traditional Chinese medicine processing, aluminum smelting and products, and equipment manufacturing.

In February 2020, after the examination and approval of the leading group of poverty alleviation in Gansu Province, Longxi County met the exit conditions of poor counties and was approved to exit.

In 2019, Longxi County achieved a gross domestic product of 7.21 billion yuan, an increase of 6% year-on-year based on comparable prices. Among them, the added value of the primary industry was 1.297 billion yuan, up 6.5% year on year; The added value of the secondary industry was 1.327 billion yuan, up 4% year on year; The added value of the tertiary industry was 4.586 billion yuan, up 6.5% year on year. The added value of the primary industry accounted for 18% of GDP, an increase of 1.9 percentage points over the previous year; The added value of the secondary industry accounted for 18.4% of GDP, down 2.5 percentage points from the previous year; The added value of the tertiary industry accounted for 63.6% of GDP, an increase of 0.6 percentage points over the previous year. The ratio of the three industrial structures is 18:18.463.6. According to the resident population, the per capita GDP was 15489.7 yuan, an increase of 4.5% over the previous year.