Arcadia is a city in Los Angeles County, California, United States located about 13 miles (21 km) northeast of downtown Los Angeles in the San Gabriel Valley and at the base of the San Gabriel Mountains. It is the site of the Santa Anita Park racetrack and home to the Los Angeles County Arboretum and Botanic Garden. The city is named after Arcadia, Greece.

In 2012, Arcadia was ranked 7th in the nation on CNN Money magazine's list of towns with highest median home costs.