Duncansville is a borough in Blair County, Pennsylvania, United States. It is part of the Altoona, PA Metropolitan Statistical Area. Duncansville is one of the communities that comprises the Altoona Urban Area. The population was 1,233 at the 2010 census.
Duncansville is located at 40°25′30″N 78°25′57″W (40.425072, -78.432435).
According to the United States Census Bureau, the borough has a total area of 0.5 square miles (1.3 km2), all of it land.
At the 2000 census there were 1,238 people, 580 households, and 338 families residing in the borough. The population density was 2,312.5 people per square mile (885.2/km²). There were 610 housing units at an average density of 1,139.4 per square mile (436.2/km²). The racial makeup of the borough was 98.47% White, 0.48% African American, 0.08% Asian, 0.08% from other races, and 0.89% from two or more races. Hispanic or Latino of any race were 0.48%.
There were 580 households, 19.5% had children under the age of 18 living with them, 44.0% were married couples living together, 10.2% had a female householder with no husband present, and 41.7% were non-families.