Paris and LA were confirmed in a unanimous vote in the Peruvian capital on Wednesday.
IOC President Thomas Bach praised the two cities for their preparations to host the world's biggest sporting event.
Reuters Edit No3269
"You have seen two games who really represent Games with sustainability and feasibility and you have seen two great projects full of passion, full of love for sport, the Olympic Games, and a great commitment to the Olympic movement."
Third time's a charm for Paris as it had fallen short with bids for 2008 and 2012.
The French capital will now be hosting the Summer Games for the first time in a century.
During the 2024 Games, beach volleyball will take place in nearby Champs de Mars, while road cycling will finish on the Champs-Elysees.
Athletics will be held at the Stade de France - the same venue for the 1998 World Cup final and Euro 2016 final.
LA, meanwhile, will be organizing its third Summer Olympics, after stints as hosts in 1932 and 1984.
Both cities initially wanted 2024, but LA gave way after the IOC promised more funding.
The stadium for football team LA Galaxy will house rugby and modern pentathlon events, and Santa Monica beach will be used for volleyball.
Ro Aram, Arirang News.