Yuba County was one of the original counties of California, formed in 1850 at the time of statehood. Parts of the county's territory were given to Placer County in 1851, to Nevada County in 1851 and to Sierra County in 1852.
According to the U.S. Census Bureau, the county has a total area of 1,667 km² (644 mi²). 1,633 km² (631 mi²) of it is land and 34 km² (13 mi²) of it is water. The total area is 2.03% water.
As of the census2 of 2000, there are 60,219 people, 20,535 households, and 14,805 families residing in the county. The population density is 37/km² (96/mi²). There are 22,636 housing units at an average density of 14/km² (36/mi²). The racial makeup of the county is 70.64% White, 3.16% Black or African American, 2.61% Native American, 7.50% Asian, 0.20% Pacific Islander, 9.95% from other races, and 5.94% from two or more races. 17.35% of the population are Hispanic or Latino of any race.
There are 20,535 households out of which 38.10% have children under the age of 18 living with them, 53.20% are married couples living together, 13.30% have a female householder with no husband present, and 27.90% are non-families. 21.70% of all households are made up of individuals and 8.20% have someone living alone who is 65 years of age or older. The average household size is 2.87 and the average family size is 3.34.
In the county the population is spread out with 31.00% under the age of 18, 10.70% from 18 to 24, 28.00% from 25 to 44, 19.60% from 45 to 64, and 10.60% who are 65 years of age or older. The median age is 31 years. For every 100 females there are 101.60 males. For every 100 females age 18 and over, there are 99.40 males.
The median income for a household in the county is $30,460, and the median income for a family is $34,103. Males have a median income of $27,845 versus $21,301 for females. The per capita income for the county is $14,124. 20.80% of the population and 16.30% of families are below the poverty line. Out of the total people living in poverty, 27.60% are under the age of 18 and 7.80% are 65 or older.