Cudahy () is a city in Milwaukee County, Wisconsin, United States, North America. The population was 18,267 at the 2010 census.
Originally known as the Buckhorn Settlement, it was renamed in the late 1800s when Patrick Cudahy purchased 700 acres (280 ha) of land in the Town of Lake, two miles (three kilometers) from the Milwaukee city limits, to build his meatpacking plant. The first village president was elected in 1895, and by 1906 Cudahy was incorporated as a city with a population of 2,556.
Cudahy is located at 42°56′54″N 87°51′40″W (42.948416, -87.861010). According to the United States Census Bureau, the city has a total area of 4.76 square miles (12.3 km2), all of it land.
At the 2010 census there were 18,267 people, 8,059 households, and 4,666 families living in the city. The population density was 3,837.6 inhabitants per square mile (1,481.7/km2). There were 8,662 housing units at an average density of 1,819.7 per square mile (702.6/km2). The racial makeup of the city was 88.8% White, 2.7% African American, 0.9% Native American, 1.4% Asian, 3.6% from other races, and 2.7% from two or more races. Hispanic or Latino of any race were 9.7%.
Out of 8,059 households, 27.0% had children under the age of 18 living with them, 40.7% were married couples living together, 11.8% had a female householder with no husband present, 5.4% had a male householder with no wife present, and 42.1% were non-families. 35.5% of households were made up of individuals, and 13.1% were one person aged 65 or older.