"It's absolutely wrong to ban athletes who have not broken the rules. It (this decision) is good," said Uchimura, a six-times world all-around champion.
"Those who dope can't complain even if they get banned for life," the 27-year-old Japanese told the Kyodo news agency.
The International Gymnastics Federation (FIG) said it was opposed to a blanket ban and on Monday announced it would establish a "pool of eligible Russian athletes" as soon as possible.
The IOC has said that individual athletes must have a clean international record on drug testing to be allowed at the Aug. 5-21 Games and ruled that competitors who had been sanctioned in the past for doping were ineligible.
Japan Olympic Committee president Tsunekazu Takeda also backed the decision.
"It's good to leave the international federations room to sanction those who can properly prove themselves clean," he said.
However, Shin Asakawa, senior director of Japan's Anti-Doping Agency, said the move could backfire on the image of the Games.
"IOC should have made a more thorough decision," he said.
"Will (clean) athletes fully accept the decision? I think this has really tarnished the value of the Olympics."
The IOC has also said there will be an immediate re-testing of all Russian athletes from Sochi 2014.
"I think it's the international federations that have the track record of doping. There could be cases where re-tests will be necessary," said Koji Murofushi, the 2004 Olympic hammer champion.
"We need the federations to move quickly to provide an environment where athletes can compete without concerns. We haven't got time, that's what worries me."
(Reporting by Nivedita Shankar in Bengaluru)
