Connellsville is a city in Fayette County, Pennsylvania, USA, 57 miles (92 km) southeast of Pittsburgh on the Youghiogheny River, a tributary of the Monongahela River. It is part of the Pittsburgh Metro Area. In 1890, 5,629 people lived in Connellsville, which was a borough at that time. 7,170 people lived in Connellsville in 1900; 12,845 in the new city of Connellsville in 1910; 13,804 in 1920; and 13,608 in 1940. The population was 9,146 at the 2000 census.
As of the census of 2000, there were 9,146 people, 3,963 households, and 2,377 families residing in the city. The population density was 4,053.5 people per square mile (1,562.5/km²). There were 4,434 housing units at an average density of 1,965.2 per square mile (757.5/km²). The racial makeup of the city was 94.54% White, 3.93% African American, 0.13% Native American, 0.33% Asian, 0.17% from other races, and 0.90% from two or more races. Hispanic or Latino of any race were 0.54% of the population.
There were 3,963 households out of which 28.2% had children under the age of 18 living with them, 40.3% were married couples living together, 15.5% had a female householder with no husband present, and 40.0% were non-families. 35.9% of all households were made up of individuals and 19.0% had someone living alone who was 65 years of age or older. The average household size was 2.28 and the average family size was 2.97.