American Idiot is the seventh studio album by American rock band Green Day, released on September 21, 2004, by Reprise Records. The album was produced by Rob Cavallo in collaboration with Green Day, an arrangement the group have been using since they signed with a major label. Recording sessions for American Idiot were made at Studio 880, in Oakland and Ocean Way Recording in Hollywood, both in California, between 2003 and 2004. A concept album, dubbed a "punk rock opera" by the band members, American Idiot follows the story of Jesus of Suburbia, a lower-middle-class American adolescent anti-hero. The album expresses the disillusionment and dissent of a generation that came of age in a period shaped by tumultuous events such as 9/11 and the Iraq War. In order to accomplish this, the band used unconventional techniques for themselves, including transitions between connected songs and some long, chaptered, creative compositions presenting the album themes.

Following the disappointing sales of their previous album Warning (2000), the band took a break and then began what they had planned to be their next album, Cigarettes and Valentines. However, recording was cut short when the master tapes were stolen; following this, the band made the decision to start their next album from scratch. The result was a more societally critical, politically charged record which returned to the band's punk rock sound following the more folk and power pop-inspired Warning, with additional influences that were not explored on their older albums. Additionally, the band underwent an "image change", wearing red and black uniforms onstage, to add more theatrical presence to the album during performances and press events.

American Idiot became one of the most anticipated releases of 2004. It marked a career comeback for Green Day, charting in 27 countries, reaching for the first time the top spot on the Billboard 200 for the group and peaking at number one in 18 other countries. It has sold over 16 million copies worldwide, making it the second best-selling album for the band (behind their 1994 major-label debut, Dookie) and one of the best-selling albums of the decade. It was later certified 6× Platinum by the Recording Industry Association of America in 2013. The album spawned five successful singles: the titular track, "American Idiot", "Holiday", "Wake Me Up When September Ends", "Jesus of Suburbia" and the Grammy Award for Record of the Year winner "Boulevard of Broken Dreams".

American Idiot was very well received critically. It was nominated for Album of the Year and won the Award for Best Rock Album at the 2005 Grammy Awards. It was also nominated for Best Album at the Europe Music Awards and the Billboard Music Awards, winning the former. Its success inspired a Broadway musical, a documentary and a planned feature film adaptation. Rolling Stone placed it at 225 on their 2012 list of the "500 Greatest Albums of All Time", and again in 2020, at 248.