Joseph Earlston Thropp (October 4, 1847 – July 27, 1927) was a Republican member of the U.S. House of Representatives from Pennsylvania.
He went to the Middle Northwest and engaged in his profession, constructing docks at Duluth, Minnesota, and Fond du Lac, Wisconsin, attaining the position of railroad division engineer.
In 1870 he moved to Conshohocken, Pennsylvania, and engaged in the manufacture of pig iron.
He retired from active business pursuits and resided in Washington, D.C., and Miami, Florida.
Interment in West Laurel Hill Cemetery in Bala Cynwyd, Pennsylvania.