The 2010 United States Census reported that El Dorado County had a population of 181,058.
In the county, the population was spread out with 26.1% under the age of 18, 6.8% from 18 to 24, 27.8% from 25 to 44, 26.9% from 45 to 64, and 12.4% who were 65 years of age or older.