The Hyeongsan River is a small river in southeastern South Korea. It flows from Doseo-myeon, Ulju-gun in Ulsan to the East Sea, covering a distance of about 63 km. The Hyeongsan watershed covers roughly 1133 km². The Hyeongsan is primarily notable for the Silla civilization which arose within its valley, centered at Gyeongju.

The Hyeongsan flows north from Ulsan into Gyeongju city, where it enters the Gyeongju Basin and is joined by the Bukcheon stream, a major tributary. It continues north into Pohang city, 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 East Sea 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.

Today the Hyeongsan continues to play a role in local transport, as it probably has for thousands of years. Although very little boat traffic is found on the river, the river valley still provides an important transportation corridor. Highways connecting Ulsan, Gyeongju and Pohang follow the river's course, as does the Donghae Nambu Line passenger railway from Gyeongju to Pohang.

See also

• List of Korea-related topics
• List of rivers of Asia