The midfielder was a key part of the Spain squad that reached the semi-finals of Euro 2020, becoming the first ever player to start six games in a single European Championship or World Cup aged 18 or below.
Instead of being given time off before the start of Barcelona's LaLiga campaign, Pedri is in Japan for the Olympic football tournament.
Spain play their first game in Group C against Egypt on July 22 before fixtures with Argentina and Australia.
Koeman told a media conference: "Pedri has played a lot. We will have to give him a break, everyone needs it during the [European] summer.
"As Pep Guardiola said, playing two important tournaments in the summer is too much, but we can't do anything.
"Pedri's European Championship was phenomenal. At the age of 18 he has played almost all the complete matches, with an impressive maturity.
"His football continues to improve and he is a very honest and calm boy. He lives for football. He is an example of how to be a young man at Barca.
"It is important for our grassroots football, that young people see that they are in a club that gives them opportunities."
Also in Spain's squad for the tournament is defender Eric Garcia, who re-joined Barca from Manchester City on a free transfer.
Koeman tipped the 20-year-old former Barca academy player to have a big impact on the first team when he is able to link up with the club following the Olympics.
"He has had a great European Championship," Koeman said.
"He comes from here and, despite his youth, he already has a lot of experience. He plays in the same position I did.
"With the ball he is very good and we can improve from behind with him. He also has projection and a great future ahead."
Meanwhile, Koeman hopes Ousmane Dembele can make a swift return from injury.
The France forward, whose contract at Camp Nou expires at the end of the 2021-22 season, is recovering from surgery on a knee injury sustained at Euro 2020 that is expected to keep him out for four months.
Dembele's career since his move to Barca from Borussia Dortmund for €105million four years ago has been blighted by injury setbacks.
The 24-year-old has managed just 54 LaLiga starts in four seasons at Camp Nou, while last season he completed 90 minutes in the league on just five occasions.
"I am very disappointed with his injury," Koeman added.
"Also, the situation with his contract is complicated. It is a pity for himself and for us.
"He brought us a lot last year, different from what we have. I hope he can come back soon."