The line of mourners spilled from the ceremonial hall at the Troyekurovskoye cemetery where Anna Politkovskaya lay in an open flower-strewn coffin.
The investigative reporter's body was then laid to rest under cold and rain-filled skies.
Among the mourners were the Norwegian, Swedish and US ambassadors as well as a who's who of Russian human rights activists but there were no high-ranking government officials.
President Vladimir Putin who has been criticised for not reacting earlier said her murder had been cruel but he also downgraded her efforts as a journalist as extremely insignificant.
Ms Politkovskaya, 48, was gunned down in what police say was a professional hit as she stepped from the lift of her apartment building in Moscow.
A star reporter at the twice-weekly Novaya Gazeta she was virtually the last Russian journalist who dared investigate atrocities in Chechnya and openly criticise Mr Putin’s rule.
At her funeral a traditional Orthodox white ribbon was wrapped around her head, where the hitman had aimed his final bullet.
Her murder has sparked deep concern throughout Europe and the US.
Letter of support
Addressing mourners, US Ambassador William Burns said he was "shocked" and repeated Washington's call for a thorough investigation.
Ms Politkovskaya's death should "remind people of the need to say the truth", he said.
Elsewhere French President Jacques Chirac sent a letter to Ms Politkovskaya's children condemning her killing and saying everything should be done to ensure that justice is done and that the assassins are found and punished.
Bulgarian national radio urged people to defend the freedom of the press by lighting candles in the Russian church in Sofia.
In Ukraine several dozen protesters placed candles outside the Russian embassy in Kiev as well as its consulate in the western city of Lviv.
Russian officials have stayed mostly silent regarding the murder.
Press freedom
Many attending the funeral fear that with Anna Politkovskaya they were also burying the last vestiges of media freedom in Russia.
"This is the funeral of a whole era," said Irena Lesnevskaya, a former head of the Ren-TV station known for her independent line.
"It was an era of conscience, truth and freedom and 10 years ago no one could have dreamt it would be crushed a decade later."
Vyacheslav Izmailov, another reporter at Novaya Gazeta, fought tears as he told mourners that the frail-looking, grey-haired mother-of-two had been like a "soldier at war".
"This is a tragedy for Russia. They executed our conscience," Yasen Zasursky, dean of Moscow state university's journalism faculty, said.
Ms Politkovskaya’s murder is the 42nd killing of a journalist in Russia since the Soviet collapse in 1991 and the 12th contract-style killing of a journalist since Mr Putin came to power in 2000.
Murder 'aimed at our country': Putin
Russian President Vladimir Putin, spoke to journalists about Ms Politkovskaya’s murder after holding talks with German Chancellor Angela Merkel in Dresden.
"Whoever committed this crime and for whatever motives, we should note that it was a crime appalling in its cruelty and must not go unpunished,” he said.
"There may have been any number of motives. Yes, this journalist was a sharp critic of the current Russian authorities. But I think that journalists should know, and experts perfectly understand, that her capacity to influence political life in Russia was extremely insignificant.
"The killing of such a person, this murder of a woman, a mother, was itself aimed at our country, against Russia, against the current authorities in Russia,” Mr Putin said.