C
- Cable in New Mutants #87
- Callisto in Uncanny X-Men #169
- Calypso in Amazing Spider-Man #209
- Cannonball in Marvel Graphic Novel #4
- Captain America in Captain America Comics #1
- Captain Britain (Brian Braddock)
- England: Captain Britain Weekly #1 (October 13, 1976)
- United States: Marvel Team-Up #65
- as Kelsey Leigh Kirkland in Avengers #77
- Captain Marvel
- as Mar-Vell in Marvel Super-Heroes #12
- as Monica Rambeau (also known as Photon or Pulsar) in The Amazing Spider-Man Annual #16 (1982)
- Captain Universe in Micronauts #8
- Carnage in The Amazing Spider-Man #361
- Cardiac in Amazing Spider-Man #344
- Cardinal in New Warriors #28
- The Cat (Greer Grant) in Claws of the Cat #1
- Cecilia Reyes in X-Men vol. 2 #65
- The Celestials in Eternals #1
- Cerebro in X-Men #7
- Cerise in Excalibur #47
- Charlie-27 in Marvel Super-Heroes #18
- Chamber in Generation X #1
- Chameleon in The Amazing Spider-Man #1
- Champion of the Universe in Marvel Two-in-One Annual #7
- The Circus Of Crime in Incredible Hulk #3
- Clea in Strange Tales #126 (name is only revealed in #146)
- Cletus Kasady in The Amazing Spider-Man #345
- Cloak in The Spectacular Spider-Man #64
- Cobra in Journey into Mystery #98
- Cobweb in Sleepwalker #3
- Collector in Avengers #28
- Colleen Wing in Marvel Premiere #19
- Colossus in Giant-Size X-Men #1
- Constrictor in Incredible Hulk #212
- Contessa Valentina Allegra de la Fontaine in Strange Tales #159
- Count Nefaria in Avengers #13
- Crossbones in Captain America #359 (in costume #360)
- Crossfire in Marvel Two-in-One #52
- Crusader in Thor #330
- Crystal in Fantastic Four #45
- Cyber in Marvel Comics Presents #85
- Cyclops in X-Men #1
Read more about this topic: List Of First Appearances In Marvel Comics Publications