Los Angeles hosted it in 1932 and 1984.
Paris and Los Angeles had been the only two candidates for the 2024 Games after Hamburg, Rome and Budapest withdrew from the race.
The IOC voted in June to award the 2028 Games at the same time as 2024.
The Californian city wanted the earlier Games because of its readiness to host while Paris said its prospective site for the Games would not be available for redevelopment after 2024.
IOC President Thomas Bach said the votes for both cities were "unanimous".
Paris - famous landmarks
Paris' bid team made liberal use of the city's most famous landmark, incorporating a stylised version of the Eiffel Tower in their logo.
When the action starts it will be the backdrop for the triathlon, marathon and open-water swimming.
The beach volleyball will take place in nearby Champs de Mars, while the road cycling will finish on the Champs-Elysees, which also hosts the final stage of the Tour de France.
The athletics will take place at the Stade de France, which staged football's 1998 World Cup final and Euro 2016 final, while the gardens of former royal palace Versailles will host the equestrian events - eventing, showjumping and dressage.
Los Angeles - familiar venue
Los Angeles' bid said it was about "what we have, not what we're going to build".
The Los Angeles Memorial Coliseum, which hosted athletics at the 1932 and 1984 Games, is to fulfil the same role in 2028.
Organisers plan to use Major League Soccer side LA Galaxy's StarHub Center for rugby and modern pentathlon events, while making use of Santa Monica beach for volleyball.
Two significant elements are yet to be constructed however - baseball ground Dedeaux Field will be converted into an open-air venue for swimming and diving.
And new MLS side Los Angeles Football Club are still building the 22,000-seater stadium that will host football matches.
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