Broad Run is a 4.3-mile-long (6.9 km) tributary of White Clay Creek located principally in New Garden Township, Chester County, Pennsylvania, in the United States.

[1] The headwaters of Broad Run are in Kaolin, just south of Pennsylvania Route 41.

Between two hills east of Landenberg, Broad Run has been dammed to form Somerset Lake, the center of a development.

Just south of the dam is the site of the Wilmington and Western Railroad's Broad Run Trestle, removed when the line to Landenberg was abandoned around 1940.

Broad Run is included in the designation of the White Clay Creek as a Wild and Scenic River.