Edwin William Keightley (August 7, 1843 – May 4, 1926) was a politician from the U.S. state of Michigan.
Keightley was born on a farm near Scott in Lagrange County, Indiana. His parents, Peter L. and Elizabeth (Winter) Keightly, emigrated from Lincolnshire, England; the former in 1831, and the latter in 1828. They settled on the farm in Van Buren township in 1836, and soon after they were married. Keightley attended the local common schools, Lagrange Academy, and Valparaiso Collegiate Institute. He was graduated from the law department of the University of Michigan at Ann Arbor in 1865 and was admitted to the bar. He commenced practice at White Pigeon, Michigan, several miles northwest of his family home in Scott. While practicing law, he was also editor of the White Pigeon Republican, a staunch advocate of Republican Party views and policy.
In 1867, Keightley moved to Constantine, Michigan, and entered into a law partnership with Judge S. C. Coffinberry, which ended in 1869, on amicable terms. He was married on July 14, 1868, to Mary Mitchell, the daughter of Thomas Mitchell, a long-time resident of Constantine, and closely identified with its manufacturing and material interests.
In 1872, he was elected prosecuting attorney of St. Joseph County, serving until January 21, 1874 when he was appointed by Michigan Governor John J. Bagley to be judge of the 15th circuit court of Michigan, comprising the counties of St. Joseph and Branch County. He was elected to the position in the spring of 1875.