Robert Downey Jr. Tony Stark / Iron Man Chris Evans Steve Rogers / Captain America Mark Ruffalo Bruce Banner / The Hulk Chris Hemsworth Thor Odinson Scarlett Johansson Natasha Romanoff / Black Widow Jeremy Renner Clint Barton / Hawkeye Tom Hiddleston Loki Samuel L. Jackson Nick Fury Cobie Smulders Agent Maria Hill Clark Gregg Agent Phil Coulson Stellan Skarsgård Erik Selvig Gwyneth Paltrow Virginia 'Pepper' Potts Paul Bettany Jarvis (voice) Alexis Denisof The Other Tina Benko NASA Scientist Jerzy Skolimowski Georgi Luchkov Kirill Nikiforov Weaselly Thug Jeff Wolfe Tall Thug M'laah Kaur Singh Young Girl Rashmi Rustagi Calcutta Woman Powers Boothe World Security Council Jenny Agutter World Security Council Arthur Darbinyan World Security Council Donald Li World Security Council Warren Kole Carrier Bridge Tech Alicia Sixtos Carrier Bridge Tech Jesse Garcia Carrier Bridge Techs Maximiliano Hernández Agent Jasper Sitwell Dieter Riesle Gala Scientist Kenneth Tigar German Old Man Walter Perez Young Shield Pilot Josh Cowdery Maintenance Guy Enver Gjokaj Young Cop Romy Rosemont Shawna Lynde Stan Lee Stan Lee Thomas Roberts Thomas Roberts Pat Kiernan Pat Kiernan Hank Amos Shield Agent (uncredited)