According to the U.S. Census Bureau, the township has a total area of 17.2 square miles (45 km2), all of which is land.

[4] Pennsylvania Route 10 is the only numbered highway serving Highland Township.

It follows Limestone Road along a north-south alignment through the western portion of the township.

[5] At the 2000 census there were 1,125 people, 433 households, and 323 families living in the township.

There were 459 housing units at an average density of 26.7 per square mile (10.3/km2).