The iconic magazine handed out its top honours at a glitzy ceremony at Claridge's Hotel in London on Tuesday night (3 November) in association with Estee Lauder and Audemars Piguet.
Other major winners included British actress Ruth Wilson, supermodel Lara Stone and Oscar-winning superstars Kate Winslet and Nicole Kidman.
The awards celebrate the creativity, intelligence and talent of women across fashion, arts and philanthropy.
Harper's Bazzar Editor-In-Chief Justin Picardie said: "The annual Harper's Bazaar Women of the Year Awards celebrate the creativity and talent of women across fashion, the arts and philanthropy. All of the winners are uniquely talented, inspiring and intelligent, and we are delighted to be honouring them."
The full list of winners is as follows:
Lara Stone, 13 magazine covers and 22 advertising campaigns this year
Lily James, Cinderella, Downton Abbey and War and Peace
Sienna Miller, Mississippi Grind, American Sniper and Burnt
Michelle Dockery, Downton Abbey
Ruth Wilson, The Affair
Clare Waight Keller, Chloe
Man of the Year
Erdem Moralioglu, Designer
Nicole Kidman, Photograph 51
Karen Elson, Save The Children
Contribution to the Arts
Hannah Rothschild, National Gallery
The presenters of the awards included: Brooke Barzun, Clemence Poesy, Danny Boyle, Dominic West, Freddie Fox, Ian McKellen, John Newman, Julia Peyton Jones, Natalie Massenet , Sam McKnight , The Countess of Wessex and Trevor Nunn.
A charity auction also took place this evening. Each winner nominated a charity of their choice and Editor-In-Chief Justine drew a random charity from a hat that would receive a generous donation from Audemars Piguet.
All women will appear in the December issue of Harper's Bazaar, featuring Lily James on the cover.