Maple Glen is a census-designated place (CDP) in Upper Dublin Township, and Horsham Township, Montgomery County, Pennsylvania, United States.

[3] According to the United States Census Bureau, the CDP has a total area of 3.1 square miles (8.0 km2), all land.

As of the 2010 census, the CDP was 85.8% Non-Hispanic White, 2.7% Black or African American, 0.1% Native American and Alaskan Native, 8.6% Asian, 0.4% were Some Other Race, and 1.0% were two or more races.

There were 2,349 housing units at an average density of 758.3 per square mile (292.8/km2).

Our Lady of Mercy was formed in 2012 by the merger of St. Alphonsus in Maple Glen, St. Anthony-St. Joseph in Ambler, and St. Catherine of Siena in Horsham.