Youngsville is a city in Lafayette Parish, Louisiana, United States. The population was 5,289 as of the 2005 Census Bureau estimates. It is part of the Lafayette Metropolitan Statistical Area.
Youngsville is located at 30°6′2″N 91°59′27″W / 30.10056°N 91.99083°W / 30.10056; -91.99083 (30.100595, -91.990707).
According to the United States Census Bureau, the city has a total area of 6.7 square miles (17.3 km²), all of it land.