Lacey Earnest Hearn (March 23, 1881 – October 19, 1969 in Fort Wayne, Indiana) was an American athlete and middle distance runner who competed in the early twentieth century. Individually he specialized in the 1500 Metres, and he won a bronze medal in Athletics at the 1904 Summer Olympics, held in St. Louis, Missouri, United States. Hearn's Compatriot James Lightbody took gold. Hearn was also a member of the American distance team which won the silver medal at the 1904 Olympics, competing in the Chicago American team in the 4-mile team race, consisting of James Lightbody, Frank Verner, Hearn, Albert Corey and Sidney Hatch.