The 32-year-old will join Madonna, Shakira and South Korean boy band BTS for the performance at the New York New Jersey Stadium on July 19, FIFA has announced.
It comes just weeks after Bieber released a surprise live album of his headline set at Coachella music festival.
The Canadian singer is best known for songs such as Baby, What Do You Mean? and Sorry, after beginning his career in his early teenage years.
The pop star has been nominated for 23 Grammy Awards and won two.
Nigerian artist Burna Boy will also feature during an 11-minute broadcast at the interval, alongside Venezuelan conductor Gustavo Dudamel, the PS 22 Chorus and Coldplay.
Coldplay frontman Chris Martin is the curator of the landmark performance, which is a first for the international soccer tournament.
The show will be staged in support of the FIFA Global Citizen Education Fund, an initiative working to raise $US100 million ($A144 million) to expand access to education and soccer for children around the world.
Characters from Sesame Street and The Muppets will be part of the show, while more than $US50 million ($A72 million) has already been raised, FIFA said, which includes $US1 from every World Cup match ticket sold "being donated to support social projects around the world".
FIFA president Gianni Infantino described the upcoming performance as a "groundbreaking spectacle" that will "celebrate football, music and our shared values, ensuring a legacy that transcends the final whistle".
"We are proud to have Justin Bieber joining Madonna, Shakira and BTS to co-headline the FIFA World Cup 2026 final half-time show in support of the FIFA Global Citizen Education Fund and our mission to expand access to quality education and football opportunities for children around the world."
Half-time entertainment has become a major feature of sporting events in the United States, notably during the Super Bowl.
Madonna headlined the Super Bowl half-time show in 2012, while Shakira shared the stage with Jennifer Lopez at the event in 2020.
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