Herval is a Brazilian municipality in the southern part of the state of Rio Grande do Sul.

Herval is situated south of the Piratini River, which was defined in 1777 as the border between the Spanish and Portuguese possessions.

The current border between Uruguay and Brazil lies further south, at the Jaguarão River.

Herval is famous for its international rodeo festival, organized every January.

This geographical article relating to Rio Grande do Sul is a stub.