Rancho Chualar was a 8,890-acre (36.0 km2) Mexican land grant in the Salinas Valley, in present day Monterey County, California. It was given in 1839 by Governor protem Manuel Jimeno to Juan Malarin.
Juan Malarin (1792 - 1849), a sea captain from Peru, came to California in 1822. As a reward for services rendered the Mexican Government, he was made a Lieutenant in the Mexican Navy. He made Monterey his home, and in 1824 he married Maria Josefa Joaquina Estrada, a daughter of José Mariano Estrada, grantee of Rancho Buena Vista. He was grantee of the two square league Rancho Guadalupe y Llanitos de los Correos in 1833, and the two square league Rancho Chualar in 1839. He also acquired Rancho Zanjones. When Malarin died in 1849, his son, Mariano Malarin, took charge of the family estate.
With the cession of California to the United States following the Mexican-American War, the 1848 Treaty of Guadalupe Hidalgo provided that the land grants would be honored. As required by the Land Act of 1851, a claim for Rancho Chualar was filed with the Public Land Commission in 1852, and the grant was patented to Mariano Malarin in 1872.
- Ogden Hoffman, 1862, Reports of Land Cases Determined in the United States District Court for the Northern District of California, Numa Hubert, San Francisco
- Diseño del Rancho Chualar
- U.S. Geological Survey Geographic Names Information System: Rancho Chualar
- A Memorial and biographical history of the coast counties of central California, Chicago; Lewis Publishing Co. 1893
- Hoover, Mildred B.; Rensch, Hero; Rensch, Ethel; Abeloe, William N. (1966). Historic Spots in California. Stanford University Press. ISBN 978-0-8047-4482-9.
- United States. District Court (California : Southern District) Land Case 110 SD
- Report of the Surveyor General 1844 - 1886
- Portraits of Isidora Pacheco and Mariano Malarín by Leonardo Barbieri