Homer LeRoy Shantz (1876–1958) was an American botanist and former president of the University of Arizona.
Born in Michigan, Dr. Shantz grew up in Colorado Springs, Colorado, and received his doctoral degree in botany from the University of Nebraska in 1905. He traveled widely, with an emphasis on the American West and Africa, and made documentary photographs wherever he went. Among Dr. Shantz’s research interests was the photographic documentation of vegetation change. He served as the President of the University of Arizona from 1928 to 1936, where he focused his attention on Arizona and the Sonoran Desert. During this period, he worked with John E. Harrison Jr. in the acquisition of land for the creation of what is now called the Saguaro National Park In 1936, he resigned after disagreements with the legislature and the Board of Regents.