Tongchang County is a kun, or county, in northeastern North Pyongan province, North Korea. It borders Pyoktong and Chagang's Usi county to the north, Unsan and Songwon to the east, Taechon to the south, and Changsong and Taegwan to the west.The Pinandok Mountains pass through northern and eastern Tongchang, contributing the county's highest point, Tanpungdoksan (단풍덕산, 1159 m). The Changsong River flows from the northwest to the southeast, on its way to join the Taedong.