The pop icon, who co-wrote and directed the romance, was joined by her W.E. stars Andrea Riseborough and James D'Arcy at London's Odeon Kensington for the film's unveiling.
W.E.'s two-tiered story centres on the affair between King Edward VIII (D'Arcy) and Wallis Simpson (Riseborough), and a contemporary romance between a married woman (Abbie Cornish) and a Russian security guard (Oscar Isaac).
Madonna brought W.E. to the UK last October for the film's BFI London Film Festival debut.
W.E. opens in UK cinemas on Friday, January 20.
> Madonna's W.E.: Andrea Riseborough stars in new trailer
> W.E. premieres in Venice - Critics split on "bold", "extraordinarily silly" drama
View Digital Spy's W.E. picture gallery below: