Mary Margaret Smith (October 7, 1893 – May 23, 2006) was an American supercentenarian and, at the time of her death at age 112 years and 228 days, Ohio's oldest verified living person. Smith also ranked fifth in the United States and was the 13th oldest person in the world. She was born in Pittsburgh and moved to Ohio in 1898. Smith had two husbands. She lived on her own until age 95 and did not move into a nursing home until the age of 108.