Lake Run is a tributary of Roaring Brook in Lackawanna County, Pennsylvania, in the United States.

The surficial geology in its vicinity consists of Wisconsinan Ice-Contact Stratified Drift, Wisconsinan Till, Boulder Colluvium, alluvium, bedrock, sand and gravel pits, fill, wetlands, peat bogs, and a lake.

The stream eventually leaves behind the border of Eagle Lake and turns northwest for several hundred feet before reaching its confluence with Roaring Brook.

[1] Lake Run joins Roaring Brook 17.50 miles (28.16 km) upstream of its mouth.

[1] The surficial geology in the vicinity of the lower reaches of Lake Run consists of bedrock consisting of conglomeratic sandstone, sandstone, and shale; Wisconsinan Ice-Contact Stratified Drift; Wisconsinan Till, a glacial till; alluvium, fill; and sand and gravel pits.

[7] Lake Run was entered into the Geographic Names Information System on August 2, 1979.