Cassiopeia or Cassiopea may refer to:
Greek mythology Cassiopeia (mother of Andromeda), queen of Aethiopia and mother of Andromeda Cassiopeia (wife of Phoenix), wife of Phoenix, king of Phoenicia Cassiopeia, wife of Epaphus, king of Egypt, the son of Zeus and Io; mother of Libya
Science Cassiopeia (constellation), a northern constellation representing the queen of Ethiopia Cassiopeia A, a supernova remnant in that constellation Cassiopea, the genus of the "upside-down" jellyfish
Arts and entertainment Film Cassiopeia (1996 film), a Brazilian CGI film Cassiopeia (2022 film), a South Korean film
Music Cassiopeia (TVXQ), the fan club of South Korean boy band TVXQ "Cassiopeia", a song by Shabütie (now known as Coheed and Cambria) from their 1999 EP The Penelope EP "Cassiopeia", a song by Joanna Newsom from her 2004 album The Milk-Eyed Mender "Cassiopeia", a song by Dragonland from their 2006 album Astronomy "Cassiopeia", a song by Sunny Lax from his 2006 EP P.U.M.A./Cassiopeia "Cassiopeia", a song by Rain from his 2006 album Rain's World "Cassiopeia", a song by Sara Bareilles from her 2013 album The Blessed Unrest "Cassiopeia", a 2023 single by Bears in Trees
Fictional characters Cassiopeia "Cassie" Sullivan, in The 5th Wave series written by Rick Yancey Cassiopeia, a magical tortoise in Michael Ende's fantasy novel Momo Cassiopeia (Battlestar Galactica), from the television series Battlestar Galactica Cassiopea (Encantadia), the first Queen of Lireo in the Encantadia fantasy series of GMA Network Cassiopeia, the mother of Octavian in The Astonishing Life of Octavian Nothing Cassiopeia, the organizer and leader of "Operation Starfall" in the Starfall Street storyline in Pokémon Scarlet and Violet
Other Casio Cassiopeia, a series of pocket PCs Cassiopeia (train), an overnight rail service in Japan USS Cassiopeia (AK-75), a cargo ship used by the United States Navy in World War II
See also Boast of Cassiopeia Casiopea, Japanese jazz fusion group Casiopea (album), the group's 1979 debut album Kassiopi, a village in Corfu