It is bordered to the north by Ryongrim and Changjin, to the east by Yŏnggwang and Hamju, to the south by Yodŏk and Chŏngp'yŏng, and to the west by Nyŏngwŏn and Tongsin.

It is drained by the Taedong River, which rises in the north part of the county before flowing west into Yŏngwŏn.

Local agriculture is dominated by dry-field farming, with maize the chief crop.

There are no railroads, but the county is served by roads which connect it to neighbouring towns via the mountain passes.

Taehung County is divided into one town (ŭp), one workers' district (rodongjagu) and 16 villages (ri).