The Tumen (Tuman) River is a river in northeast Asia, on the border between China and North Korea in its upper reaches, and between North Korea and Russia in its lower stretches. The name of the river comes from the Jurchen tumen, which means "ten thousand."

The river is 521 km long, rising in the Changbai (Changbaek) Mountains and flowing into the Sea of Japan.

See also

• Geography of China
• Geography of North Korea
• List of Korea-related topics