| Hyeongsan River | |
 Hyeongsan River from Dong Bridge in Gyeongju, Korea. | |
| Korean name | |
|---|---|
| Hangul | 형산강 |
| Hanja | |
| Revised Romanization | Hyeongsangang |
| McCune–Reischauer | Hyŏngsan'gang |
The Hyeongsan River is a river in southeastern South Korea. It flows from Baeyanggol Valley (배양골), Wolpyeong-ri (월평리/月坪里), Dudong-myeon (두동면/斗東面), Ulju County in Ulsan to the Sea of Japan, covering a distance of about 62 km. The Hyeongsan watershed covers roughly 1,167 km2 (Jo 1987:35).
The Hyeongsan flows north from near the northern border of Greater Ulsan into Gyeongju, where it enters the Gyeongju Basin and is joined by the Bukcheon stream (북천/北川), a major tributary. It continues north into Pohang, and in Angang-eup of Pohang it is joined by the Gigyecheon flowing from the north and turns abruptly eastward. From there runs east and slightly north until it meets the Sea of Japan at Pohang Harbor. The estuary of the Hyeongsan has been covered by the massive industrial development around the port of Pohang, including the POSCO steel mill.