Rancho Fernandez was a 17,806-acre (72.06 km2) Mexican land grant in present day Butte County, California given in 1846 by Governor Pío Pico to Dionisio Zenon Fernandez and Máximo Zenon Fernandez.  The grant extended along the west bank of the Feather River, and encompassed present day Oroville and Thermalito.
The four square league grant was made to brothers Dionisio Z. Fernandez and Máximo Z. Fernandez who were sons of José Zenon Fernandez, grantee of Rancho Quito.
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 Fernandez was filed with the Public Land Commission in 1852, and the grant was patented to Dionisio Z. Fernandez, Máximo Z. Fernandez, Josiah Belden, and William R. Basham in 1867.
- 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 Fernandez
- United States. District Court (California : Northern District) Land Case 377 ND
- Report of the Surveyor General 1844 - 1886
- Henshaw v. Bissell, U.S. Supreme Court,85 U.S. 18 Wall. 255 255 (1873)