Joseph Smith Harris (April 29, 1836 – June 1, 1910) was an American surveyor, civil engineer, and railroad executive. Largely self-taught, he worked on several projects for the U.S. government, including the Coast Survey of the Mississippi Sound in 1854–56 and the Northwest Boundary Survey of 1857–61. He worked his way through a considerable number of adventures to become president of the Reading Railroad, which he brought back from its 1893 bankruptcy.