Dangtu County (simplified Chinese: 当涂县; traditional Chinese: 當涂縣; pinyin: Dǎngtu Xiàn) is the only county under the jurisdiction of Ma'anshan City in eastern Anhui Province, People's Republic of China.

Dangtu is one of the longest established counties in eastern China and formed part of the Taiping Prefecture during the Ming and Qing Dynasties.

Dangtu County has a long history of more than 2000 years as a county.It was called Danyang (丹阳) in Qin Dynasty. While in Sui Dynasty it got the name as "Dangtu" 当涂. A famous poet named Xie Tiao (谢朓) once praised Dangtu County as the place of beautiful mountains and rivers. Li Bai had come to Dangtu seven times. His uncle used to be the governor of Dangtu County. There is a memorial to the famous Chinese poet, Li Bai (aka Li Po c.700-762), who is said to have drowned at Dangtu after attempting to embrace the reflection of the moon. While this is only a local legend, Dangtu people always feel familiar with many poems Li Bai wrote because the beautiful scenaries described in those poems are actually those of the places in which they always lived all their lives.