Junan County, subordinate to Linyi City of Shandong Province, is located at the junction of Lushu and Jiangsu in the southeast of Shandong Province, in the east of Linyi City, adjacent to Lanshan District of Rizhao City in the east, Ganyu District of Lianyungang City of Jiangsu Province in the south, adjacent to Hedong District of Linyi City in the west, and adjacent to Ju County of Rizhao City in the north. Junan County has a total area of 1,752 square kilometers. According to the seventh census, Junan has a permanent population of 841,000.

Juan County was classified into Jucounty of Langya County along with the Justate in the Qin and Sui dynasties. It belonged to JuCounty of Mi Prefecture in Henan Province in the Tang Dynasty, to Ju Prefecture of Qingzhou in the Ming Dynasty, and to Ju Prefecture of Yizhou in the Qing Dynasty. In January of the thirty years of the Republic of China (1941), the anti-Japanese democratic government of Junan County was established, named for Juxian southern county. As of March 2021, Junan County has jurisdiction over one subdistrict and 15 towns, with 266 administrative villages and 741 natural villages in total.

In 2021, the GDP of Junan County was 33.938 billion yuan. Revenue in the general public budget was 2.61 billion yuan.