Michael or Mike Day may refer to:
- Michael Day (guitarist), American guitarist
- Michael Day (cricketer) (born 1974), Australian cricketer
- Mike Day (darts player) (born 1955), New Zealand darts player
- Mike Day (cyclist) (born 1984), American bicycle motocross (BMX) racer
- Michael S. Day, member of the Massachusetts House of Representatives
- Michael Day (paleoanthropologist), British anatomist and paleoanthropologist
- Mikey Day (born 1980), American comedian
See also
edit- Michael Bay, an American filmmaker
- Michael Davis (disambiguation)