Rosslyn Farms is a suburban borough located 5 miles (8 km) west of Pittsburgh in Allegheny County, Pennsylvania, United States.

[3] Rosslyn Farms is bordered by Carnegie to the south, Robinson Township to the west, and Thornburg to the north.

[4] According to the United States Census Bureau, the borough has a total area of 0.6 square miles (1.6 km2), all land.

16.8% of all households were made up of individuals, and 5.9% had someone living alone who was 65 years of age or older.

Founded in 1902 by the Chartiers Land Company, Rosslyn Farms was developed by William Parrish.