Mayang River or Kali Mayang is a river located in the south of East Java and flows into the Indian Ocean at a cape in Watuulo, Jember Regency, in the southern coastal area of Java.

[1][2] The river originates in the southwest of Mount Raung.

It has a length of approximately 146 km (91 mi)[3] and a watershed area covering 1,113 km2 (430 sq mi).

[1][4]