John Plankinton, American businessman and industrialist, also noted for philanthropy (b. 1820)
John Plankinton (March 11, 1820 – March 29, 1891) was an American businessman. He is noted for expansive real estate developments in Milwaukee, including the luxurious Plankinton House Hotel designed as an upscale residence for the wealthy. He was involved with railroading and banking. The Plankinton Bank he developed became the leading bank of Milwaukee in his lifetime. He was involved in the development of the Milwaukee City Railroad Company, an electric railway.

Plankinton was a Milwaukee-based meatpacking industrialist. He started this trade as a butcher for his general store operating in the center part of the city. He was the city's leading meat packer after his first year in the grocery business. He expanded this industry and eventually became acquainted with the meatpacking industrialist Philip D. Armour forming a company with him that lasted for 20 years.

Plankinton was noted for his generous philanthropy. He donated the land for the construction of the Perseverance Presbyterian church and supported the formation of a soup kitchen in Milwaukee for the poor that included the daily supply of meat needed. He also financed the construction of the first Milwaukee public library.