Lou Costello
- Birthday: 1906-03-06
- Deathday: 1959-03-03
- Place of birth: Paterson, New Jersey, USA
- Also know as: Louis Francis Cristillo
Louis Francis Costello (March 6, 1906 – March 3, 1959) was an American actor and comedian best known as half of the comedy team of Abbott and Costello, with Bud Abbott. Costello was famous for his bumbling, chubby, clean-cut image that has appealed to many Americans over the decades, and for his shouted line of "HEEEEYYY ABBOTT!!."
