The opening ceremony of the 2012 Summer Olympics took place on the evening of Friday 27 July 2012 in the Olympic Stadium, London, during which the Games were formally opened by Queen Elizabeth II. As mandated by the Olympic Charter, the proceedings combined the ceremonial opening of this international sporting event with an artistic spectacle to showcase the host nation's culture. The spectacle was entitled Isles of Wonder and directed by Academy Award-winning British film director Danny Boyle.

The Olympic Games ceremonies of the Ancient Olympic Games were an integral part of these Games; the modern Olympic games have opening, closing, and medal ceremonies. Some of the elements of the modern ceremonies date back to the Ancient Games from which the Modern Olympics draw their ancestry. An example of this is the prominence of Greece in both the opening and closing ceremonies. During the 2004 Games, the medal winners received a crown of olive branches, which was a direct reference to the Ancient Games, in which the victor's prize was an olive wreath. The various elements of the ceremonies are mandated by the Olympic Charter, and cannot be changed by the host nation. This requirement of seeking the approval of the International Olympic Committee (IOC) includes the artistic portion of opening and closing ceremonies.