Ambrose Swasey (December 19, 1846 – June 15, 1937) was an American mechanical engineer, inventor, entrepreneur, manager, astronomer, and philanthropist.

The close friends Warner and Swasey built their homes next to each other on Euclid Avenue in Cleveland, a street that was known as "Millionaire's Row".

In addition to army ordnance contracts, the firm of Warner & Swasey became notable for their work on astronomical observatories and equipment.

In 1885, Swasey completed work at McCormick Observatory on the 45-foot dome, which was the largest in the world, and had a unique, 3 shutter design.

Other donations made by Swasey include the Swasey Chapel at Denison University in Granville, Ohio (1924), a bandstand in Exeter by architect Henry Bacon (1916), a library building to Colgate Rochester Divinity School and the endowment of a chair for a professor of physics at the Case School of Applied Sciences.