Director Asif Kapadia and producer James Gay-Rees, who previously made the film 'Senna', accepted the award from 'Star Wars' actress Daisy Ridley, 'Slumdog Millionaire' actor Dev Patel, and thanked everyone involved in the making of the film.
Asif added: "This film was all about Amy. We wanted to show who she really was… a beautiful girl, special, witty girl, someone who needed looking after."
The film exploring her life and tragic demise became the UK's most successful ever documentary when it was released last summer, despite Amy's father Mitch voicing his unhappiness with the film, which he thought concentrated on the negative aspects of Amy's life.
Mark won for his role in Stephen Spielberg's wartime thriller 'Bridge of Spies', also beating Mark Ruffalo, as well as fellow Brits Tom Hardy and Christian Bale.
Kate Winslet had been nominated for her role in 'Steve Jobs', but she lost out to Alicia Vikander for 'The Danish Girl'.
Costume designer Jenny Beavan was another home-grown victor, for her work on 'Mad Max: Fury Road', although she was on the receiving end of some strange looks as she approached the stage to collect her award.
Click here for the complete list of Oscar Winners 2016