Río Grande is a town and municipality of Puerto Rico located on the eastern edge of the Northern Coastal Valley, north of Las Piedras, Naguabo and Ceiba; east of Loíza and Canóvanas and west of Luquillo. Río Grande is spread over eight barrios and Río Grande Pueblo. It is part of the San Juan-Caguas-Guaynabo Metropolitan Statistical Area. A big portion of El Yunque National Forest, including El Yunque's peak, is located within the municipality.

Río Grande barrio-pueblo is a barrio and the administrative center (seat) of Río Grande, a municipality of Puerto Rico. Its population in 2010 was 1,772.