Placerita Canyon State Park, Nature park in Los Angeles County, United States.

Placerita Canyon State Park lies along Placerita Creek between the Newhall and Sand Canyon neighborhoods of Santa Clarita, on the north slope of the western San Gabriel Mountains. The canyon runs east-west on the Placerita Fault and holds sandstone and metamorphic formations, seasonal streams, chaparral, and coast live oak woodland. Riparian trees include arroyo willow, cottonwood, and California sycamore. A brown sign at 19152 Placerita Canyon Road marks the entrance.

In 1842, Francisco López discovered gold flakes on wild onions, an event that preceded California's major gold rush by several years. This early finding drew attention to the region as a place of mineral wealth.

The canyon's name comes from the Spanish placerita, a diminutive of placer, the term for shallow sandy ground where gold or other metals collect. The Tataviam lived in the canyon and the surrounding Santa Clarita Valley before European settlement. Near the park are historic and still active movie ranches, including Melody Ranch and Golden Oak Ranch.

The park offers multiple hiking trails suited for different skill levels and a nature center with educational exhibits. Visitors can learn about local wildlife and ecosystems at the center.

A small pool of naturally filtered white oil seeps beside the trail from the Nature Center up to Walker Ranch. Prospectors in the late 19th century were startled to find oil that was transparent rather than black; the park notes this seep is unknown anywhere else in the world.