Furnace Run is a tributary of Catawissa Creek in Columbia County, Pennsylvania, in the United States.

The stream itself is considered to be a high quality coldwater fishery and Class A Wild Trout Waters.

It flows northeast in a valley and enters Main Township after approximately a thousand feet.

A short distance downstream, it receives an unnamed tributary and turns east-northeast and crosses a road.

[8] The Pennsylvania Department of Environmental Protection classifies Furnace Run as a high-quality coldwater fishery.

[3] The stream is considered by the Pennsylvania Fish and Boat Commission to be Class A Wild Trout Waters from its headwaters to its mouth.