SM1 can refer to:
- SM-1, a nuclear reactor
- SM1, a postcode district within the SM postcode area, in Sutton, Greater London
- A surface-to-air missile, RIM-66 Standard (SM-1MR) or RIM-67 Standard (SM-1ER)
- VR Class Sm1, a type of train operated by the VR Group
- Spider-Man 1, also known as just Spider-Man, the first film in the Spider-Man film series
- Scary Movie, the first film in the Scary Movie series
- Superman (film), the first Superman film