Percival Lawrence Lowell (/ˈləl/; March 13, 1855 – November 12, 1916) was an American businessman, author, mathematician, and astronomer. He founded the Lowell Observatory in Flagstaff, Arizona. He started the effort that led to the discovery of Pluto 14 years after his death.

His reputation was damaged by his belief in canals on Mars. This idea was counter-attacked by Alfred Russel Wallace.