J
- J. Jonah Jameson in The Amazing Spider-Man #1
- Jigsaw in The Amazing Spider-Man #161
- Jocasta in Avengers #162
- Joseph in Uncanny X-Men #327
- Jotunheim in Journey into Mystery #114
- Jubilee in Uncanny X-Men #244
- Juggernaut in X-Men #12
Read more about this topic: List Of First Appearances In Marvel Comics Publications