Harry Day (disambiguation)
Harry Day was a Royal Marine and RAF pilot during the Second World War, prisoner of war and noted escapee.
Harry Day may also refer to:
- Harry Day (politician), British labour party politician, Member of Parliament 1924–1931, 1935–1939
- Harry Day (rugby union), Welsh international rugby union forward
- Harry G. Day, American chemist and professor
- Harry S. Day, Ohio State Treasurer