- Adaptational Context Change: The U2 song "Pride" is turned from a celebration of the individual's role in effecting social justice to an appeal for a one-night stand.
- AFI's 100 Years... Series:
- Cut Song: Kylie Minogue recorded two other songs for the film - covers of Olivia Newton-John's "Physical" and Donna Summer's "I Feel Love".
- Deleted Scene: A scene establishing the "Gothic Tower" as a bordello was cut. It involved dancers in S&M gear performing Grace Jones' "Slave to the Rhythm", "Warm Leatherette", and "Pull Up to the Bumper".
- Fake Nationality: The French characters are played by Australian and British actors (and one Colombian actor), and an Argentinian character is played by a Polish actor. Most of them use their own accents, except Nicole Kidman who puts on an English one.
- Non-Singing Voice: Averted with Ewan McGregor and Nicole Kidman, who performed their own singing, but played straight with Jim Broadbent (Zidler) whose more operatic notes are dubbed by singer Anthony Weigh.
- Sleeper Hit: Made a modest $50 million at the box office (maybe not-so-modest considering the musical genre was sagging), but became an even bigger hit on DVD via word-of-mouth.
- What Could Have Been:
- The Green Fairy was initially more monstrous and drew inspiration from Iggy Pop, Marilyn Manson, and Ozzy Osbourne before evolving into her final incarnation as Kylie Minogue. Ozzy himself supplied that the warped roar her voice turns into.
- Early drafts of the script had Satine with a three-year-old child, and Christian would be narrating the story to the child.
- An even earlier draft would have had a Triang Relations plot between the Duke, Satine and Christian - where the Duke would get both of them hooked on morphine.
- Catherine Zeta-Jones and Heath Ledger were contenders to play Satine and Christian. Courtney Love also lobbied hard for the role, and called losing it to Nicole Kidman one of her biggest career regrets. She did however allow "Smells Like Teen Spirit" to be covered for the film, a rare instance of her allowing late husband Kurt Cobain's work to be used.
- Other possible Christians included Leonardo DiCaprio, Jake Gyllenhaal, Hugh Jackman, and Ronan Keating. Other possible Satines included Drew Barrymore, Hilary Swank, Kate Winslet and Renée Zellweger. Tim Wheeler also auditioned for Christian, which led him to write the track "Orpheus".
- Rowan Atkinson and Alan Cumming were considered for Toulouse-Lautrec. John Leguizamo was originally considered for The Argentinean.
- Elijah Wood auditioned by doing a song-and-dance number but he failed to land a part.
- "Come What May" was originally written for William Shakespeare's Romeo + Juliet, but cut from the film and reused here. It's the only original piece of music, but could not get nominated for "Best Original Song" since it was written for another film.
- The first musical number was to be "Father & Son" between Christian and his father. Cat Stevens however objected to the sexual content in the film and would not allow the song to be used. The special edition DVD has the scene included in the complete script.
- The Duke was originally going to sing a rendition of Frank Sinatra's "My Way", but it never happened. There's a reference to this in the finale, as the Duke repeatedly yells "my way!"
Trivia / Moulin Rouge!