IOC officials have ruled that because Russian athletes have been caught out so many times taking drugs, all athletes are now assumed to be guilty, and must provide proof they have a history of being drug-free.
It is now up to sport federations to vet Russia's individual Olympic candidates.
With only 12 days to go, it's a crushing blow and affirms that Russia has carried out an elaborate cheating scheme under government orders.
Olympic committee president Thomas Bach said it was "a shocking new dimension in doping" with an "unprecedented level of criminality."
President Putin says the decision is politically motivated and meant to undermine Russia's standing in the world.
Each athlete's drug testing history will be analysed by a reliable anti-doping authority outside Russia.
Russia's Minister for Sport Vitaly Mutko said he was confident the majority of athletes would meet the criteria, but he won't be going to the Rio Games after IOC officials said last week that no employee of Russia's Sports Ministry would be welcome.
However, 67 Russian athletes are planning to apply to the IAAF to compete in the games.