The Court of Arbitration for Sport said on Thursday it had rejected Russia's appeal against the exclusion of its track and field athletes from the Rio Games starting on Aug. 5.
"CAS rejects the claims/appeal of the Russian Olympic Committee and 68 Russian athletes," CAS said in a statement.
The ruling by the CAS, sport's highest tribunal, will be taken into consideration by the International Olympic Committee (IOC) as it ponders whether to impose a blanket ban on Russia from all sports.
The affair has triggered a crisis in world sport, with Russian President Vladimir Putin speaking of the risk of a split in the Olympic movement.
Russian track and field athletes were banned from international competition in November after an independent commission set up by the World Anti-Doping Agency (WADA) found rampant state-sponsored doping in Russian athletics.
The ban was imposed by the IAAF, the global governing body for athletics, which reconfirmed it last month, saying there were still considerable problems with anti-doping in Russia.
The appeal was launched by the Russian Olympic Committee (ROC) and 68 Russian athletes who said they were being punished despite not having failed drugs tests, and that they should be eligible to compete in Rio.
On Monday, another WADA report revealed evidence of systematic and widespread state-sponsored doping by Russian competitors before and at the 2014 Sochi Winter Olympics. This has prompted the IOC to consider banning Russia from Rio altogether.
The IOC is expected to reach a final decision within the next week and has said it will take the CAS ruling into account.

Minister says regrets court ruling

Russian Sports Minister Vitaly Mutko said on Thursday he regretted that the Court of Arbitration in Sport rejected a legal challenge by a group of Russian athletes against a ban on them competing in the Rio Olympics, Interfax news agency reported.
"I regret this decision," the agency quoted Mutko as saying. "Unfortunately, a certain precedent has been established for collective responsibility," for doping violations by individual sportspeople.
Mutko said Russian officials will consider what steps to take in the light of the court's decision, and that things could not be left as they are, Interfax reported.

We did everything possible: Russian athletics chief

Dmitry Shlyakhtin, the head of the Russian Athletics Federation (ARAF), said on Thursday his organisation had done everything it could to ensure Russian athletes were able to compete at the Rio Olympics, the R-Sport news agency cited him as saying.

Court ruling "funeral of athletics": Isinbayeva

Olympic pole vault champion Elena Isinbayeva said on Thursday a decision by the Court of Arbitration for Sport to reject a challenge by a group of Russian athletes against a ban on them competing in the Rio Olympics amounted to a "funeral of athletics", TASS news agency reported.