Lanshan County, under the jurisdiction of Yongzhou City of Hunan Province, is located in the southern border of Hunan Province and on the north side of the middle part of Nanling Mountains. It is known as "Chuwei Yuetou" and is an important gateway to the coastal areas of Guangdong from the southwest of Hunan Province. Blue Mountain is located in the eastern foot of Jiuyi Mountain, the terrain tilted from the southwest to the northeast, hills, hills and Yi mountain areas interlocking with each other, mainly mountains, is a typical mountain counties. Lanshan County borders Linwu County in the east, Jianghua Yao Autonomous County and Lianzhou City of Guangdong Province in the south, Ningyuan County in the west and Jiahe County in the north. From the county seat, it travels 33 kilometers south along Yonglian Highway to the provincial border of Guangdong. Lanshan County is 420 kilometers to Changsha in the north and 320 kilometers to Guangzhou in the south, where provincial Highway lines 322 and 314 intersect. The total area of the county is 1806 square kilometers. According to the seventh census, the permanent population of Lanshan County was 329,909 as of midnight on November 1, 2020.

In 1998, Lanshan County won the title of "Model Unit of National Unity and Progress". In 2012, Lanshan County was named "Hunan Province population and Family planning work advanced County". In 2012, Lanshan County entered the top ten advanced counties in Hunan Province.

In September 2015, the Implementation Plan of the Hunan Provincial Department of Land and Resources to Promote the Reform of the economic System directly administered by the Province was issued. According to the plan, Lanshan County became the pilot county (city) of Hunan Land and Resources Province directly administered county economic system reform.

In July 2020, the National Association of Health Care decided to name Lanshan County as the 2017-2019 National Health County. In 2020, the GDP of Lanshan County reached 127.47 billion yuan, an increase of 4.0 percent.