The Geum River is a river in Chungcheongbuk-do that flows through Chungcheongnam-do, then becomes part of the border in between there and Jeollanam-do before emptying into the Yellow Sea near Gunsan city.

In the area of Buyeo County, it bears the name Baengmagang (백마강, 白馬江), which means White Horse River. Numerous legends associate the ancient kingdom of Baekje with the Baengmagang. A very famous song of the sin minyo tradition, Kkumkkuneun Baengmagang (꿈꾸는 백마강, "Dreaming Baengmagang"), is about this stretch of the river.

The river's Korean name ("Gold River") is a homonym of the word for "diamond" (금강; 金剛) and should not be confused with Kŭmgang Mountain (금강산; 金剛山; "Diamond Mountain") in North Korea.