The 2011 SummerSlam was the 24th annual SummerSlam professional wrestling pay-per-view (PPV) event produced by WWE. It was held for wrestlers from the promotion's Raw and SmackDown brand divisions. The event took place on August 14, 2011, at the Staples Center in Los Angeles, California for the third consecutive year. It was the final WWE pay-per-view event held before the dissolution of the original brand extension, which was introduced in March 2002, although the brand split would be reintroduced in July 2016.

The card consisted of eight matches, but only seven were televised. In the main event, WWE Champion CM Punk defeated WWE Champion John Cena to become the Undisputed WWE Champion with Triple H as the special guest referee, after which, Alberto Del Rio cashed in his Money in the Bank briefcase and defeated CM Punk to win the WWE Championship. In another prominent match, Randy Orton defeated Christian in a No Holds Barred match to regain the World Heavyweight Championship. SummerSlam attracted a sellout crowd of 17,404 fans at Staples Center in Los Angeles, grossing more than $1 million, marking the highest grossing SummerSlam held at Staples Center. The event garnered 296,000 pay-per-view buys, down from 350,000 buys the previous year.

SummerSlam is an annual pay-per-view (PPV) produced every August by WWE since 1988—in April 2011, the promotion ceased going by its full name of World Wrestling Entertainment, with "WWE" becoming an orphaned initialism. Dubbed "The Biggest Party of the Summer", it is one of the promotion's original four pay-per-views, along with WrestleMania, Royal Rumble, and Survivor Series, referred to as the "Big Four". It has since become considered WWE's second biggest event of the year behind WrestleMania. The 2011 event was the 24th SummerSlam and was scheduled to be held on August 14, 2011, at Staples Center in Los Angeles, California for the third consecutive year. It featured wrestlers from the Raw and SmackDown brand divisions.

Much like the previous year's SummerSlam, WWE promoted the event with its SummerSlam Axxess fan convention, held at the Nokia Plaza in LA Live on August 13 and 14. R&B singer Cee Lo Green performed both "'Bright Lights Bigger City", the official theme song for the event, and his hit "Forget You" during the broadcast. The commentators for this event were Michael Cole, Jerry Lawler, and Booker T.

The professional wrestling matches at SummerSlam featured professional wrestlers performing as characters in scripted events pre-determined by the hosting promotion, WWE. Storylines between the characters were produced on WWE's weekly television shows Raw and SmackDown with the Raw and SmackDown brands—storyline divisions in which WWE assigned its employees to different programs.

The main feud headed into SummerSlam from the SmackDown brand was between Christian and Randy Orton, over Christian's World Heavyweight Championship. At Extreme Rules in May, Christian defeated Alberto Del Rio in a ladder match to win the vacant World Heavyweight Championship for the first time, only to lose it to Orton on the May 6 episode of SmackDown. After two unsuccessful attempts at regaining the title from Orton at the Over the Limit and Capitol Punishment pay-per-views, Christian finally won the championship for the second time at the Money in the Bank event in July, after he spat in Orton's face, provoking the latter to kick Christian in the groin and get himself disqualified; as per pre-match stipulations enacted by Christian, he won the title. On the July 29 episode of SmackDown, the new Chief Operating Officer of WWE, Triple H, scheduled a title defense by Christian against Orton in a No Holds Barred match at SummerSlam.

The main event from the Raw brand for SummerSlam would pit John Cena against CM Punk for the WWE Championship. In the weeks leading to the Money in the Bank pay-per-view in July on Raw, Punk announced the expiration of his WWE contract on the night of the Money in the Bank, en route lambasting WWE for failing to promote him as the "best wrestler in the world", and threatened some high authority figures like WWE Chairman, Vince McMahon, of defeating Cena and leaving WWE with the championship. At Money in the Bank, Punk pinned Cena to win the title, and even after McMahon tried to have Alberto Del Rio – who had won the Raw Money in the Bank briefcase earlier that night – cash in his contract against Punk. The latter nevertheless left the arena with the championship. The following night on Raw, McMahon dismissed Punk's claim to the title, and announced an 8-man tournament to decide the new WWE Champion. Also, on the same night, Triple H relieved McMahon of his duties, and assumed control over WWE as the Chief Operating Officer just as the chairman was about to fire Cena. On the July 25 episode of Raw, Rey Mysterio defeated The Miz in the finals to become the WWE Champion but lost it later on the same night against Cena. After the match, Punk returned to WWE with the title belt he had won at Money in the Bank, initiating a title dispute between Cena and Punk. As they were now two wrestlers with a claim to the WWE Championship, a one-on-one match between Punk and Cena was scheduled for SummerSlam to determine the undisputed WWE Champion. On the August 8 episode of Raw, Triple H made himself the special guest referee for the Undisputed WWE Championship match.

The Divas rivalry heading into SummerSlam was between Kelly Kelly and Beth Phoenix over the WWE Divas Championship. On the August 1 episode of Raw, Phoenix won a Divas battle royal to become the #1 Contender for the Kelly's Divas Championship at SummerSlam. Phoenix turned heel after her victory by attacking Kelly in and out of the ring, and later told Kelly that "her days as the cute, blonde little bimbo are over". On the following week, Phoenix defeated Eve Torres in singles action, but was attacked by Kelly after the match.