IOC announced that Russia would be automatically readmitted so long as there were no more doping violations.
The International Olympic Committee (IOC) confirmed on Wednesday that it had reinstated Russia after the remaining tests of the country's athletes at the Pyeongchang Winter Olympics were all returned negative.
Russians competed as neutrals at the Games after the IOC suspended the country's Olympic Committee (ROC) in December, saying it had found evidence of an "unprecedented systematic manipulation" of the anti-doping system.
On Sunday, the IOC announced that Russia, which has repeatedly denied any state involvement in doping, would be automatically readmitted so long as there were no more doping violations.
"The final notification of all remaining test results from the Olympic Athlete from Russia (OAR) delegation has been received," said the IOC in a statement on Wednesday. "The IOC can confirm that all the remaining results are negative.
"Therefore, as stated in the Executive Board decision of Feb. 25, the suspension of the Russian Olympic Committee is automatically lifted with immediate effect."
The decision had been announced earlier in comments by ROC president Alexander Zhukov on state television.
"The Russian Olympic Committee has had its rights fully restored," he said. "It's a decision of the utmost importance for us."
A team of 168 Russians competed as part of a neutral 'Olympic Athlete from Russia' (OAR) team in Pyeongchang but two of them failed drug tests - medal-winning curler Alexander Krushelnitsky and bobsledder Nadezhda Sergeeva.
They had all been required to prove they were clean before the Games.
Under the neutrality rules, the Russians were unable to wear national uniforms or have their anthem played at medal presentations, although the ice hockey team sang the national anthem on Sunday.