Byrns is a surname. Notable people with the surname include:
Elinor Byrns (1876—1957), American lawyer and pacifist, co-founder of the Women's Peace Society
Harold Byrns (1903–1977), German-American conductor and orchestrator
Joseph W. Byrns, Jr. (1903–1973), U.S. attorney and politician
Joseph W. Byrns, Sr. (1869–1936), U.S. Democratic politician
Samuel Byrns (1848–1914), U.S. member of Congress from Missouri
