Beal said on Twitter that he is dedicating his summer to getting into the "best physical shape" for next season. He called the invitation from USA Basketball "the ultimate honor."
Beal is the latest player to decline the chance to play for the U.S. in Rio. NBA Finals MVP LeBron James, regular-season MVP Stephen Curry, Russell Westbrook, Chris Paul, James Harden and others have said they won't go.
Beal, 22, has a career average of 16 points a game. He has been injury-prone during his four years in the NBA, playing in 247 of a possible 328 regular-season games.
Wizards teammate John Wall removed himself from consideration when he had knee surgery after the season ended.
Information from The Associated Press was used in this report.