San Lucas Island National Park (Spanish: Parque Nacional Isla San Lucas) is an island located off the Pacific shore of Costa Rica in the Gulf of Nicoya. It is part of the Puntarenas district of Puntarenas Canton of the province of Puntarenas. Formerly housing a brutal prison, now abandoned, the island was designated as a National Park on August 2020 by decree 9892 and managed under the Central Pacific Conservation Area.