Frio River (Spanish: Río Frío) is a river of Costa Rica, Alajuela province.

The Frio River is a river located in Costa Rica, emerging from the northern slope on the Caribbean side of the country.

It emerges from the foothills of the Tenorio Volcano and travels along the plains of the Guatusos in the north of Costa Rica.

In the lower part of its basin lies Caño Negro Wildlife Refuge.

This article related to a river in Costa Rica is a stub.