Mile Run is a tributary of White Deer Creek in Union County, Pennsylvania, in the United States.

Wild trout naturally reproduce within the stream and numerous bryophyte species have been observed in its vicinity.

Mile Run begins in a valley between Fawn Ridge and Pine Flat in West Buffalo Township.

At this point, the stream turns south for several tenths of a mile, passing between Pine Flat and Little Mountain.

A short distance further downstream, the stream reaches its confluence with White Deer Creek.

[3] The White Deer Valley Railroad, which was incorporated on December 11, 1900, passed in the vicinity of Lick Run.