Flight 45/Flight 045/Flight U-45 is an airline flight number that has had multiple accidents and incidents. It may refer to:
- Eastern Air Lines Flight 45 - A mid-air collision involving a Douglas DC-3-201C and a Douglas A-26C-35-DT Invader in 1945
- Aeroflot Flight U-45 - An Ilyushin Il-18 which flew into a mountain in February 1970
- Flying Tiger Line Flight 45 - A Douglas DC-8-63F that crashed 2000 feet short of the runway in July 1970
- Air Europa Flight 045 - A Boeing 787-9 Dreamliner which was rocked by severe in-flight turbulence in 2024