- Wasp/"Susan" (Hope Van Dyne) (First appearance as Wasp) (Main story and flashback) (Death)
- Ant-Man (Scott Lang) (Main story and flashback)
- Dr. Hank Pym (Main story and flashback) (As Ant-Man in flashback only) (Death)
- Janet Van Dyne (First full appearance) (Main story and flashback) (As the Wasp in flashback only) (Death)
- Cassie Lang (Main story and flashback)
- X-Con Security Consultants (First appearance)
- Ant-Man's Ants
- Ghost (Ava Starr) (First appearance) (Main story and flashback)
- Sonny Burch (First appearance)
- Uzman (First appearance)
- Knox (First appearance)
- Anitolov (First appearance)
- Dr. Bill Foster (First appearance) (Main story and flashback)
- Rose (Only appearance) (Only in flashback)
- S.H.I.E.L.D. (Only in flashback)
- Captain America (Steve Rogers) (Mentioned)
- Maggie Lang
- Jim Paxton
- Avengers (Mentioned)
- Hydra (Mentioned)
- Elihas Starr (Only appearance; dies) (Only in flashback)
- Catherine Starr (Only appearance; dies) (Only in flashback)
- George Washington (Mentioned)
- George Jefferson
- MI6 (Mentioned)
- Captain Daniel Gooobler (First appearance)
- Stan Lee
Races and Species:
- Earth-199999 (Main story and flashback)
- Earth (Main story and flashback)
- United States of America (Main story and flashback)
- Germany (Mentioned)
- Argentina (Only in flashback)
- Quantum Realm
- Earth (Main story and flashback)
- Sokovia Accords (Mentioned)
- Ant-Men's Suits and Helmets (Main story and flashback)
- Wasps' Suits and Bio-Synthetic Wings (Main story and flashback)
- Pym Particles
- Pym Discs
- Hank Pym's Portable Lab (First appearance)
- Ghost's Suit (First appearance) (Main story and flashback)
- Quantum Tunnel (First appearance)
Plot not yet listed
Additionally, Divian Ladwa, Goran Kostić and Rob Archer portray Uzman, Anitolov, and Knox, respectively. Sean Kleier, Benjamin Byron Davis, and Suehyla El-Attar appear as FBI agents Stoltz, Burleigh, and Pearson, respectively. Michael Cerveris and Riann Steele portray Elihas and Catherine Starr, respectively. Tim Heidecker makes a cameo as Captain Daniel Gooobler. Stan Lee makes a cameo as a pedestrian whose car is shrunk. Julia Vera-Andrews portrays Luis' grandmother. Darcy Shean appears as Rose the nanny. Brian Huskey cameos as Cassie's teacher. The Best Show hosts Tom Scharpling and Jon Wurster make cameos as Burch's SUV drivers.
- Ant-Man co-writer Adam McKay stated he would have a contribution to the film in some sort of capacity.
- Filming for this film began on August 1, 2017, and wrapped on November 19, 2017.
- The film takes place two years after Captain America: Civil War.
- Marvel Studios announced Ant-Man and the Wasp on October 8, 2015, almost a year after the original slate of Phase 3 films in the Marvel Cinematic Universe was first announced.
- Early on, the film included a flashback scene of Hank Pym and Bill Foster's younger years working together, in which audiences would've been able to actually see Foster growing in size. The idea was scrapped, according to director Peyton Reed, because it was from a narrative perspective "too much of a left turn."
- Writers Chris McKenna and Erik Sommers were told at one point to add a piece of dialogue about Hope Van Dyne losing her cat, which would have had ramifications in Avengers: Endgame. McKenna believes it's possible that instead of a rat, Hope's cat would have been responsible for setting up the Quantum Tunnel to free Ant-Man from the Quantum Realm.