Mary Scott Dimmick Lord Harrison (April 30, 1858-January 5, 1948) was the second wife of the 23rd United States president Benjamin Harrison. She was 25 years younger than him.

Ms. Dimmick married the former president in 1896. His first wife, Caroline Harrison had died in 1892. They had one daughter, Elizabeth Harrison, born February 21, 1897. Benjamin Harrison died in 1901 after 5 years of marriage.