Elenco

• Sigourney Weaver — Lt. Ellen Louise Ripley
• Tom Skerritt — Arthur Koblenz Dallas
• Ian Holm — Ash
• John Hurt — Gilbert Ward Kane
• Harry Dean Stanton — Samuel Elias Brett
• Yaphet Kotto — Dennis Monroe Parker
• Veronica Cartwright — Joan Marie Lambert
• Helen Horton — Mother (voice)
• Bolaji Badejo — The Alien