Ostara is the hypothetical Old High German name for the goddess Eostre, of which little is known. The modern holidays Easter and Eastertide are thought to be related to the worship of this goddess.
Ostara can also refer to:
- The Neopagan and Wiccan festival celebrated around the spring equinox, Ostara
- The asteroid 343 Ostara, named after the Teutonic goddess
- The American Artemis class attack cargo ship USS Ostara (AKA-33) (1944–1946), named after the asteroid
- The 20th century occult and Aryanist publication of Lanz von Liebenfels, Ostara (magazine)
- The neo-folk music group Ostara (band)