The California Botanic Garden (formerly the Rancho Santa Ana Botanic Garden) is a botanical garden in Claremont, California, in the United States, just south of the San Gabriel foothills. The garden, at 86 acres (35 ha), is the largest botanic garden in the state dedicated to California native plants. It contains some 70,000 native Californian plants, representing 2,000 native species, hybrids and cultivars. The seed bank has embryos for the thousands of rare plants.

The garden has an active research department, specializing in systematic botany and floristics. The herbarium of Pomona College, housed at the garden, was transferred from the college in 1996. It holds over 1,200,000 specimens. The journal Aliso is published by the organization semiannually. The garden offers graduate degrees in botany through Claremont Graduate University.

The garden originated in 1927 when Susanna Bixby Bryant established a native garden on her rancho in Orange County. The garden relocated to Claremont in 1951. The facility, run by a non-profit organization, was open to the public with free admission for 58 years; in 2009 an admission fee was implemented. In 2019, the garden was renamed "California Botanic Garden" to better represent the contents of its collections.

• Bernard Field Station
• John R. Rodman Arboretum in Claremont, California
• List of California native plants
• List of botanical gardens and arboretums in California
• List of botanical gardens in the United States

• Everett, Percy, C. (1957). A summary of the culture of California plants at the Rancho Santa Ana Botanic Garden, 1927-1950. Claremont, Calif., RSABG.{{cite book}}: CS1 maint: multiple names: authors list (link)

• Rancho Santa Ana Botanic Garden
• Gallery
• yorbalindahistory.org Developed by the Yorba Linda Public Library. Includes a collection of historic magazine and newspaper articles and pamphlets about the garden.

34°06′42″N 117°42′58″W / 34.11167°N 117.71611°W / 34.11167; -117.71611