Preserver can refer to:
- Life preserver, a personal flotation device or lifebuoy
- Life preserver, a type of club (weapon)
- , a Canadian navy ship
- , Protecteur-class supply ship
- , leadship of the Fairmile-support depot ships
- , a U.S. navy ship
- Preserver (Elfquest), a race in the fantasy comic Elfquest
- Preservers (Star Trek), a Star Trek species
- Preserver (Star Trek), a novel by William Shatner