Green Lantern is a 2011 American superhero film directed by Martin Campbell, from a screenplay by Greg Berlanti, Michael Green, Marc Guggenheim, and Michael Goldenberg. Ryan Reynolds stars as Hal Jordan / Green Lantern, a test pilot who is selected to become the first human member of the Green Lantern Corps, an intergalactic police force. He is given a ring that grants him superpowers and must confront Parallax, a being who threatens to upset the balance of power in the universe. The film also stars Blake Lively, Peter Sarsgaard, Mark Strong, Angela Bassett, and Tim Robbins.

The film first entered development in 1997; progress remained stalled until Berlanti was hired to write and direct in October 2007. Martin Campbell was brought on board in February 2009 after Berlanti was forced to vacate the director's position. Most of the live-action actors were cast between July 2009 and February 2010, and filming took place from March to August 2010 in Louisiana. The film was converted to 3D during its post-production stage. This was the first DC film since Catwoman (2004) not to be involved with Legendary Pictures.

Green Lantern was released in the United States on June 17, 2011, by Warner Bros. Pictures. The film received generally negative reviews from critics for its script, tone, visual effects, and unfaithfulness to the source material, and underpeformed at the box office, grossing $237 million against a production budget of $200 million. It was also originally intended to start a film franchise based on DC characters. However, due to the film's critical and commercial disappointment, Warner Bros. scrapped plans for a sequel, opting instead to use Man of Steel (2013) as the official start of the DC Extended Universe, two years after Green Lantern's release.