Over the centuries, many people have made use of the open spaces and plentiful water, plant and animal resources of the Chino Hills. Prior to European contact, the Gabrielino Indians, who lived along the Santa Ana River basin, set up temporary camps for gathering acorns, elderberries, walnuts and other seeds.
After the Spanish founded Mission San Gabriel in 1771, the Chino Hills were used extensively for grazing by mission cattle. During the Mexican Republic era, the hills were used as spillover grazing from such surrounding Mexican ranchos as Santa Ana del Chino and La Sierra Yorba. After Mexico ceded California to the United States in 1848, the land was still used primarily for grazing.
Private land acquisition began in the 1870s and continued into the 1890s. In 1948, the 1,720-acre Rolling M Ranch was established and the land leased to nearby landowners for cattle grazing. Some late nineteenth and early twentieth century oil exploration and mining activity also took place in the northwestern section of what is now the park. A ranch house, barn, and several windmills and watering troughs serve as reminders of the cattle ranching days.
In 1977, the California legislature passed a resolution directing California State Parks to conduct a study on acquiring Chino Hills land for park purposes. A local citizen group, Hills for Everyone, worked closely with California State Parks and the legislature to create the park with an initial acquisition of 2,237 acres. In 1984, the State Park and Recreation Commission officially declared the area a unit of the State Park System. Since that date, numerous land acquisitions from various private landowners have expanded the park to its present acreage.