Margaret Sixel is a South African-born, Australian film editor. She was born in South Africa. She is best known for her work as editor on feature film projects such as Babe: Pig in the City (1998), Happy Feet (2006), and Mad Max: Fury Road (2015), and won an Oscar for editing Mad Max: Fury Road. Her body of film work extends across numerous genres, such as documentary features, live-action short films, animated comedies, and action epics. In 1994, Sixel was appointed film editor for Kay Pavlou’s dramatized Australian documentary, Mary (1994), about Australian saint Mary MacKillop. Three years later, Sixel edited the television documentary 40,000 Years of Dreaming (1997) for director George Miller. During the early 2000s, Sixel edited two short films under the direction of English-born Australian filmmaker Rachel Ward, The Blindman’s Bluff (2000) and The Big House (2001). Sixel’s remaining three feature film projects have since all been collaborations between herself and director George Miller, beginning in 1998 with Babe: Pig in the City, and followed by Happy Feet (co-edited alongside Christian Gazal) in 2006, and Mad Max: Fury Road in 2015.

In 2016, Sixel won an Academy Award for her work on editing Mad Max. She also won the Best Editing award at the 21st Critics' Choice Awards, the 2016 ACE Eddie Award for Best Edited Feature Film – Dramatic, and the BAFTA Award for Best Editing.