Mercersburg Academy is an independent college-preparatory boarding and day high school in Mercersburg, Pennsylvania, in the United States. Founded in 1893, the school enrolls approximately 444 students in grades 9–12, including postgraduates, on a campus about 90 miles northwest by north of Washington, D.C.

Mercersburg is a borough in Franklin County, Pennsylvania, United States. The borough is 72 miles (116 km) southwest of Harrisburg, the state capital.