Ischigualasto Provincial Park (Spanish: Parque Provincial Ischigualasto), also called Valle de la Luna ("Valley of the Moon" or "Moon Valley"), due to its moon-like appearance, is a provincial protected area in the north-east of San Juan Province, north-western Argentina, limiting to the north with the Talampaya National Park, in La Rioja Province. Both areas belong to the same geological formation, the Ischigualasto Formation (sometimes called the Ischigualasto-Talampaya Formation). Established on 3 November 1971, the park has an area of 60,370 ha (603.7 km; 233.1 sq mi).

In 2000, UNESCO included Ischigualasto and Talampaya National Park among its World Heritage Sites.

The name Ischigualasto is derived from the extinct Cacán language, spoken by an indigenous group referred to as the Diaguita by the Spanish conquistadors and means "place where the moon alights". Another hypothesis gives the name "Ischigualasto" a Quechua origin, meaning "dead land", although some scholars have proposed Huarpe roots.