Milroy is a census-designated place (CDP) that is located in the Kishacoquillas Valley of Mifflin County, Pennsylvania, United States.

[3] According to the United States Census Bureau, the CDP has a total area of 0.7 square miles (1.8 km2), all land.

As of the census[5] of 2000, there were 1,386 people, 582 households, and 388 families residing in the CDP.

There were 614 housing units at an average density of 917.9 per square mile (354.4/km2).

29.7% of all households were made up of individuals, and 15.6% had someone living alone who was 65 years of age or older.