The 2012 Extreme Rules was the fourth annual Extreme Rules professional wrestling pay-per-view (PPV) event produced by WWE. It took place on April 29, 2012, at the Allstate Arena in the Chicago suburb of Rosemont, Illinois. It included Brock Lesnar's first WWE in-ring match since WrestleMania XX in 2004. The concept of Extreme Rules is that the event features various hardcore-based matches.

Eight professional wrestling matches were scheduled on the event's card and one pre-show match was livestreamed on YouTube. Only four of the main card's matches were contested under a hardcore stipulation. In the main event, John Cena defeated Brock Lesnar in an Extreme Rules match. Elsewhere on the card, CM Punk defeated Chris Jericho in a Chicago Street Fight to retain the WWE Championship, and Sheamus defeated Daniel Bryan in a two out of three falls match to retain the World Heavyweight Championship.

The pay-per-view received universally positive reviews, with the main event and two world championship matches drawing high praise from critics and fans. The event received 263,000 buys, up 25.8% from the 209,000 buys for the previous year's event, whereas the next year's event received 231,000 buys, a drop of 12.1%. This was the only WWE pay-per-view event to receive a rating of TV-14 since WWE's transition to TV-PG in July 2008 and has been ranked as one of WWE's best events ever.