This list encompasses fictional characters and species who are parasites and/or parasitoids.

A

• Alien (sometimes referred to as a xenomorph),^[1] parasitoid species that is the primary antagonist of the Alien franchise
• Aparoid

B

• Baby (Dragon Ball)
• Bellum (The Legend of Zelda)
• Bezoar (Buffy the Vampire Slayer)
• Biollante
• Blackrock (comics)
• Brood (comics)
• William Birkin

C

• Carnage (character)
• Ceti eel - creature in the film Star Trek II: The Wrath of Khan, invading the human brain^[2]
• Chimera Anima - blob-shaped parasitic aliens in manga Tokyo Mew Mew, infecting animals and changing them into monsters

D

• Deathspiral Butterfly - parasitoid butterfly in Shadowrun
• Destoroyah
• DNAlien (Ben 10)

E

• Eclipso
• Edriss 562

F

• Flood (Halo)

G

• Goa'uld - the main antagonists in Stargate and Stargate SG-1
• Gravemind
• Gregor Samson (Skullgirls)
• Gae Bolga (Skullgirls)

H

• Headcrab
• Heartless (Kingdom Hearts)
• Hedorah

I

• Illyria (Angel)
• Imhotep (character)

J

• Jiger

L

• Left Hand (Vampire Hunter D)
• Lavos
• Las Plagas
• Leviathan (Skullgirls)

M

• Metroid (species)
• Metroid Prime (character)
• Mummudrai
• MUTO

N

• Hinako Ninomiya
• Nemesis (Resident Evil)
• Neurax Worm (Plague Inc.)
• Cassandra Nova
• N'Tal ("Second Soul", 1995 episode of The Outer Limits)

P

• Parallax (comics)
• Parasite (comics)
• Parasite - 1982 3-D film
• Pod People (Invasion of the Body Snatchers)
• Parasytes (manga)

R

• Regulan bloodworm - mentioned in various episodes of Star Trek, sometimes causing sickness but also medically useful

S

• Sublime (Marvel Comics)
• Symbiote (comics)
• Silents (Doctor Who)
• Sekhmet (Skullgirls)

T

• Thread, filaments of a space-borne spore that devours organic matter in the Dragonriders of Pern
• Trill symbiont in Star Trek: Deep Space Nine, a symbiotic life form that gives its host all the memories of its previous hosts

U

• Unity (Superman: The Animated Series)

V

• Venom (Marvel Comics character) Spider-Man's archenemy from outer space
• Visser Three, the main antagonist character in the Animorphs book and television series
• Jason Voorhees (See Jason Goes to Hell: The Final Friday)

X

• X Parasite

Y

• Yeerk, the main antagonist race in book and television series Animorphs