The Communists, who won 57 seats in the 450-seat Russian parliament, filed the suit in late May saying that the election results, announced by the Central Election Committee, had been falsified by the ruling United Russia party, which garnered 64.3% of the votes.
The Communist Party said that they and other political factions had been subject to media discrimination in favor of United Russia, and cited numerous violations in the election campaign and during voting.
The Communists also requested that the court question 20 witnesses, including Central Election Commission chairman Vladimir Churov, Unite Russia top council's chairman Boris Gryzlov and Prime Minister Vladimir Putin. The court rejected the request saying that "everything is clear without them," the party's chief lawyer Vadim Solovyov said.
The Communists have pledged to appeal the Supreme Court's decision.
"We are likely to appeal to the European Court," Solovyov said, describing the Supreme Court's actions as "polite but biased."
Russia's top court rejected a similar appeal from the Union of Right Forces (SPS), which collected about 1% of the vote, on July 4.
