Nangang was settled in 1735 by Fujianese, especially in the present villages of Nangang, Sanchong, and Dongxin. The placename was Great Jia'na Fortress (大加蚋堡), Nangang-Sanchong Port (南港三重埔). The Qing era name of Lamkang'a (南港仔; Pe̍h-ōe-jī: Lâm-káng-á; literally: "southern port"), refers to its position on Keelung River.
In 1920, during the Japanese era, Nangang was part of Naiko Village (内湖庄), Shichisei District (七星區), Taihoku Prefecture. In December 1945, after the handover of Taiwan to the Kuomintang, the administrative levels were changed to Neihu Township (內湖鄉), Qixing District (七星區), Taipei County. July 6 the following year, as proposed by Mayor Que Shankeng (闕山坑), Nangang was separated into its own township (南港鎮). In 1967, it became a district of Taipei.