The Mărcușa (also: Cernat) is a right tributary of the Râul Negru in Romania.

[1][2] It flows into the Râul Negru between the villages Mărcușa and Surcea.

[3] Its length is 24 km (15 mi) and its basin size is 89 km2 (34 sq mi).

[2] The following rivers are tributaries to the river Mărcușa (from source to mouth):

This article related to a river in Covasna County is a stub.