Draped in traditional Islamic green fabric, 282 coffins were lowered into fresh graves alongside 600 victims buried in March.
Each coffin held bones dug up from dozens of mass graves, including the remains of two 14-year-old boys and two elderly men who were in their 70s when gunned down.
In July 1995, Bosnian Serb forces captured the predominantly Muslim town, which had been declared a United Nations "safe area" two years earlier.
They then divided women from the men who were then summarily executed. In just a few days, up to 8,000 Muslims were killed.
So far, the remains of 1,000 victims have been identified by DNA analysis.
More than 5,000 body bags are still awaiting identification, while new mass graves continue to be discovered.
For the first time, a Bosnian Serb government delegation headed by Prime Minister Dragan Mikerevic attended the anniversary ceremony.
Bosnia's top Muslim cleric, Mustafa Ceric, led the prayers.
Tears running down her face, Avdic Sefija stood by the grave of her husband, killed as he desperately tried to flee through the woods.
"Even though he will be buried here today, I will not find peace until I return to Srebrenica," the 51-year-old woman, who now lives in the Bosnian capital Sarajevo said.
Her only son is still missing after the massacre.
Srebrenica is now part of Bosnia's Serb republic and security is provided by Bosnian Serb police monitored by NATO-led peacekeepers.
Only some 220 Muslims have so far returned to Srebrenica, now inhabited mainly by Serb refugees from other parts of the Balkan country, where roughly 200,000 people died during the conflict (1992-1995).
"The grave in Srebrenica will be the only thing I have left from my son," Husein Pitarevic, whose son Adnan, killed at 14, said.
Pitarevic, who is still living as a refugee in Sarajevo, said he would like to follow his dead son's body and also return to Srebrenica.
Others fear return to the Serb-controlled part of the country where the town is located since many Muslim returnees have been the target of harassment.
"I would never come back to Srebrenica, I could not stand to look at my Serb neighbors whom I remember separating men from women," in July 1995, Raza Atic, whose grandfather Avdulah killed at 75 was also to be buried, told AFP.
War crimes charges
Most Serbs still deny the massacre ever happened, while a report by the Bosnian Serb government last year also questioned its veracity, provoking worldwide outrage.
The U.N. war crimes tribunal in The Hague has accused wartime Bosnian Serb leader Radovan Karadzic and his military commander Ratko Mladic of genocide for the massacre. Both men remain at large.
Karadzic is believed to be hiding in eastern parts of Republika Srpska, which is one of the two entities created to run the country under the agreement that ended the war. The other is the Muslim-Croat Federation.
The tribunal has sentenced Radoslav Krstic, the Bosnian Serb general who led the attack on Srebrenica, to 46 years in prison.
Former Yugoslav president Slobodan Milosevic is also on trial in The Hague for genocide and war crimes relating to the war.