The singer-songwriter appears on the Jay-Z-curated soundtrack for the film, contributing the new song 'Young And Beautiful'.
Del Rey said: "It was an honour to work with Baz Luhrmann on his amazing adaptation of one of the most extraordinary books ever written.
"The movie is highly glamorous and exciting; Rick Nowels and I were thrilled to write the song for the film."
Jay-Z previously said: "The Great Gatsby is that classic American story of one's introduction to extravagance, decadence and illusion.
"It's ripe for experimentation and ready to be interpreted with a modern twist. The imagination Baz brought to Moulin Rouge! made it a masterpiece, and Romeo + Juliet's score wasn't just in the background; the music became a character.
"This film's vision and direction has all the makings of an epic experience."
Luhrmann added: "F Scott Fitzgerald's novel is peppered with contemporary music references specific to the story's setting of 1922.
"While we acknowledge, as Fitzgerald phrased it, 'the Jazz Age,' and this is the period represented on screen, we - our audience - are living in the 'hip-hop age' and want our viewers to feel the impact of modern-day music the way Fitzgerald did for the readers of his novel at the time of its publication."
As well as Del Rey and Jay-Z, Luhrmann worked alongside Florence Welch and The xx, who wrote their new songs to picture.
The score for the film has been composed by Craig Armstrong, who previously worked with Luhrmann on Moulin Rouge! and William Shakespeare's Romeo + Juliet.
The soundtrack is released on May 6 in standard and deluxe digital and physical editions via Interscope Records.
The full track list for The Great Gatsby's standard soundtrack album is as follows:
1. '100$ Bill' - Jay-Z
2. 'Back To Black' - Beyoncé x André 3000
3. 'Bang Bang' - will.i.am
4. 'A Little Party Never Killed Nobody (All We Got)' - Fergie + Q Tip + GoonRock
5. 'Young And Beautiful' - Lana Del Rey
6. 'Love Is The Drug' - Bryan Ferry with The Bryan Ferry Orchestra
7. 'Over The Love' - Florence + The Machine
8. 'Where The Wind Blows' - Coco O of Quadron
9. 'Crazy in Love' - Emeli Sandé and The Bryan Ferry Orchestra
10. 'Together' - The xx
11. 'Hearts A Mess' - Gotye
12. 'Love Is Blindness' - Jack White
13. 'Into the Past' - Nero
14. 'Kill and Run' - Sia
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