Hewitt competed in his third olympics in London 2012 where he entered the men's singles event and defeated Ukrainian Sergiy Stakhovsky in the first round. He was the only Australian in any tennis event to progress past the first round. In the second round Hewitt took out 13th seeded Croatian Marin Čilić. In the third round Hewitt stunned the tennis world when he won the first set against the number 2 ranked Novak Djokovic, he would end up falling in three sets. He also sent an application to the International Olympic Committee to enter the men's doubles competition with Chris Guccione but the application was rejected. Following his men's doubles rejection, Hewitt decided to apply for a spot in the mixed doubles competition with Sam Stosur. The pair were granted entry and defeated Polish pair Marcin Matkowski and Agnieszka Radwańska in the first round. In the quarterfinals, Hewitt/Stosur faced British pair Andy Murray and Laura Robson, they would lose the encounter.