Robert Downey Jr. as Tony Stark / Iron Man

Chris Hemsworth as Thor

Mark Ruffalo as Bruce Banner / Hulk

Chris Evans as Steve Rogers / Captain America

Scarlett Johansson as Natasha Romanoff / Black Widow

Jeremy Renner as Clint Barton / Hawkeye

James Spader as Ultron (voice)

Samuel L. Jackson as Nick Fury

Don Cheadle as James Rhodes / War Machine

Aaron Taylor-Johnson as Pietro Maximoff / Quicksilver

Elizabeth Olsen as Wanda Maximoff / Scarlet Witch

Paul Bettany as Jarvis / Vision

Cobie Smulders as Maria Hill

Anthony Mackie as Sam Wilson / The Falcon

Hayley Atwell as Peggy Carter

Idris Elba as Heimdall

Linda Cardellini as Laura Barton

Stellan Skarsgård as Erik Selvig

Claudia Kim as Dr. Helen Cho

Thomas Kretschmann as Strucker

Andy Serkis as Ulysses Klaue

Julie Delpy as Madame B

Stan Lee as Stan Lee

Henry Goodman as Dr. List

Chris Luca as Fortress Soldier

Brian Schaeffer as Strucker Mercenary

Dominique Provost-Chalkley as Zrinka

Isaac Andrews as Costel

Gareth Kieran Jones as Sokovian Acid Student

Chan Woo Lim as Dr. Cho's Assistant

Minhee Yeo as Dr. Cho's Assistant

Bentley Kalu as Klaue's Mercenary

Julian Bleach as Ballet Instructor

Christopher Beasley as Johannesburg Cop

Vuyo Dabula as Johannesburg Cop

Nondumiso Tembe as Johannesburg Driver

Kabelo Thai as Johannesburg Onlooker

Lele Ledwaba as Johannesburg Onlooker

Mandla Gaduka as Johannesburg Onlooker

Harriet Lenabe as Johannesburg Onlooker

Beulah Hashe as Johannesburg Onlooker

Musca Kumalo as Johannesburg Onlooker

Mathapelo September as Johannesburg Onlooker

Antony Acheampong as Johannesburg Elevator Passenger

Chioma Anyanwu as Johannesburg Elevator Passenger

Ben Sakamoto as Cooper Barton

Imogen Poynton as Lila Barton

Isabella Poynton as Lila Barton

Ingvild Deila as World Hub Tech

Sunny Yeo as Korean Train Passenger

Namju Go as Korean Train Passenger

Mina Kweon as Korean Train Passenger

Earl T. Kim as Korean Train Passenger

Arthur Lee as Korean Train Passenger

Verity Hewlett as Sokovian Family

Michael Matovski as Sokovian Family

Alma Noce as Sokovian Family

Riccardo Richetta as Sokovian Family

Constanza Ruff as Sokovian Woman

Monty Mclaren-Clark as Tub Family Child

Julia Krynke as Sokovian Driver

Tony Christian as Sokovian SUV Driver

Ian Kay as Sokovian SUV Passenger

Barry Aird as Sokovian Police Captain

Aaron Himelstein as Specialist Cameron Klein

Kerry Condon as Friday (voice)

Jaiden Stafford as Nathaniel Pietro Barton

Josh Brolin as Thanos (uncredited)

Robert J. Fraser as Youth (uncredited)

Lou Ferrigno as Hulk (voice) (uncredited)

Zakk Pierce as Sokovian Boy (uncredited)