Joseph Reynolds (June 11, 1819 – February 21, 1891) was an American entrepreneur and founder of the Diamond Jo Line, a transportation company which operated steamboats on the upper Mississippi River.

Reynolds established a successful leather-tanning operation in Chicago before becoming a grain trader in the upper-Mississippi River corridor.

As a legacy, he established an endowment for the University of Chicago in order to build a clubhouse: the Reynolds Club, most recently used as a student union.

[3] In 1860, Reynolds sold his Chicago tannery and entered extensively into the grain business along the Mississippi, moving to McGregor, Iowa, and made his home there.

This allowed Reynolds to move his grain along the river to the railhead at Prairie du Chien, Wisconsin on his own timetable.

Then the Minnesota Packet Company made a deal with Reynolds: if he agreed to sell the 123-foot sternwheeler, they would extend better freight service to him in the future.

The next year he purchased three more steamers and a fleet of barges, calling his new company the "Chicago, Fulton, and River Line."

Just as before, Reynolds acquired vessels to provide for his own shipping needs on a small segment of the upper Mississippi River.

[1] However, with this new enterprise, Reynolds increased the tonnage he hauled on behalf of other shippers, and expanded the scope of his river operations, running anywhere from St. Louis to St.Paul.

His estate included real estate, steam packets, grain elevators, mining properties in Arizona, California, Colorado, Kansas, Illinois, Iowa and Missouri, and the Hot Springs Railroad, a 24-mile-long (39 km) narrow gauge line running from Malvern, Arkansas, to Hot Springs, Arkansas.

[7] He is buried at a family plot in Mount Hope Cemetery (Chicago) with his wife, Mary Morton Reynolds, and his son, Blake.

[9] His wife, Mary Morton, inherited the Diamond Jo Line, and after she died in 1895, it was acquired by a partnership led by her brother.