According to the census of 2008, there were 57,925 people, 18,162 households, and 14,220 families residing in the city. The population density was 2,382.4/km² (6,167.8/mi²). There were 18,473 housing units at an average density of 800.5/km² (2,072.4/mi²). The racial makeup of the city was 64.02% White, 1.11% Black or African American, 0.46% American Indian or Alaskan Native, 25.76% Asian, 0.40% Native Hawaiian or other Pacific Islander, 3.95% from other races, and 4.30% from two or more races. 10.68% of the population were Hispanic or Latino of any race.
There were 18,162 households out of which 34.3% had children under the age of 18 living with them, 63.4% were married couples living together, 10.5% had a female householder with no husband present, and 21.7% were non-families. 16.0% of all households were made up of individuals and 5.5% had someone living alone who was 65 years of age or older. The average household size was 3.00 and the average family size was 3.35. More than 1/3 of all the housing units in the city are those other than single-family homes, such as condominiums or apartments.
In the city the population was spread out with 23.5% under the age of 18, 7.9% from 18 to 24, 30.1% from 25 to 44, 27.2% from 45 to 64, and 11.3% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 95.6 males. For every 100 females age 18 and over, there were 93.0 males.
The median income for a household in the city was $78,729, and the median income for a family was $90,335. Males had a median income of $60,399 versus $43,089 for females. The per capita income for the city was $48,521. About 1.6% of families and 2.3% of the population were below the poverty line, including 3.2% of those under age 18 and 3.0% of those age 65 or over.
In addition to the I-405 freeway which bisects the city, Fountain Valley is served by several bus lines operated by the Orange County Transportation Authority. Bus routes 33, 35, 37, 70, 72, 74, and 172 cover the city's major streets.
Most of the major roads are equipped with bicycle lanes, especially around Mile Square Park, which offers wide bike paths along the major streets that mark its boundary. Dedicated bike paths along the Santa Ana River run from the city of Corona to the Pacific Ocean.