American illustrator associated with the Ashcan School. She was known for the authenticity she brought to her work for the major magazines of the early 20th century.

May Wilson displayed marked artistic ability from an early age. In 1889, when she was barely out of high school, she helped found the Women's Art Club (later the National Association of Women Artists) in New York City. She attended Oberlin (Ohio) College (1889–92) but left before graduating in order to enroll in the Art Students League in New York, where she remained for more than four years, under the tutelage of such artists as Robert Henri (Henri, Robert), John Henry Twachtman (Twachtman, John Henry), and William Merritt Chase (Chase, William Merritt). In 1899 Wilson traveled to Paris to study with James McNeill Whistler (Whistler, James McNeill).

Her career as a professional illustrator began in New York in 1901, when she sold her first work to periodicals such as Harper's Bazaar. The quarters she shared with two other artists at the Sherwood Studios became a popular gathering place for artists and writers. In 1903 she married James M. Preston, a painter and associate of Henri, John Sloan (Sloan, John French), George Luks (Luks, George), and others in the so-called Ashcan School. May Preston exhibited frequently with them—adopting their style of urban realism—and with the more formally organized Society of Illustrators, of which she was the first, and for many years only, woman member.

Preston was represented at the famous Armory Show of 1913. Her commercial illustrations appeared in the Saturday Evening Post, the Woman's Home Companion, the Delineator, McClure's, and other leading magazines. The failing market for her work during the Great Depression, together with a skin infection that made work difficult, largely ended her career.