Yongdeng, known as Lingju and Zhuanglang in ancient times, belongs to Lanzhou, Gansu Province, located in the central part of Gansu Province, northwest of Lanzhou, with an east longitude of 102°36 'to 103°45' and north latitude of 36°12 'to 37°07'. The county covers a total area of 6090 square kilometers. Gaolan County and Jingtai County of Gansu Province in the east, Minhe Hui Tuzu Autonomous County of Qinghai Province in the west, Honggu District and Xigu District of Lanzhou City in the south, Tianzhu Tibetan Autonomous County in the north. The longest distance from south to north is 107 kilometers, and the widest distance from west to east is 101 kilometers, with a total area of 6,090 square kilometers. According to the seventh census, the permanent population of Yongdeng County was 285,549 as of midnight on November 1, 2020.

Yongdeng County currently has jurisdiction over 3 townships, 13 towns, 11 communities and 200 administrative villages (among which Zhongchuan and Qinchuan townships are entrusted to the administration of Lanzhou New Area), with a total population of 427,800, among which 293,200 agricultural population, mainly Han, Hui, Manchu, Tibetan, Mongolian, Turkish, Dongxiang and other 18 ethnic groups. Ethnic minorities account for 4.5% of the total population.

On January 25, 2019, Yongdeng County was selected as the national "Safe Agricultural Machinery" demonstration County in 2018. On April 28, 2019, the government of Gansu Province approved the withdrawal of Yongdeng County from poverty. In 2020, the annual GDP of Yongdeng County reached 11.261 billion yuan.