The funerals were held in Goma, the main city in North Kivu province, which has been plagued by fighting between M23 (March 23 Movement) rebels and the DRC armed forces.
The mainly Tutsi-led M23 resumed its armed campaign in the Democratic Republic of Congo in 2021 and has seized swathes of territory.
Thirty-five coffins were lined up for the ceremony at Goma's largest stadium, AFP journalists saw.
Burials later took place in Kibati, around 10 kilometers (six miles) north of the provincial capital, in a special cemetery for victims of conflict.
On May 3, bombs struck huts in the Mugunga camp for displaced people on the outskirts of Goma.
Humanitarian sources and an official from the camp put the death toll at 15, but a government minister said 35 people had died and 37 were injured.
The DRC and the United States have accused the M23 of being behind the attack on the camps, whose residents had been driven out of their villages by an M23 offensive.
"Twenty two of those (killed) were children... they were killed, victims of the barbarism of Rwanda," Patrick Muyaya, government spokespeman and minister for media and communications, said on X.
Muyaya, who attended the funerals on Wednesday, had previously called the blasts a "war crime."
The DRC government has also condemned the bombing as an "act of terrorism" and called for "substantial political and economic sanctions" against Rwanda, which it accuses of supporting the M23 rebels.
The US State Department has also accused Rwandan forces of joining M23 rebels in the blasts on the camp and called on Kigali to punish those responsible.
The Rwandan government has dismissed the US accusation as "ridiculous," saying Rwanda has a "professional army" that would "never attack" a camp for displaced people.
Espoir Bwesha, 23, said he lost his 19-year-old brother David in the blasts.
David had been "resting inside his hut when a bomb fell on him," Bwesha told AFP ahead of the ceremony.
"I want the enemy to be driven out and for peace to return," he said, adding he did not want any more "heavy weapons" to be placed near camps for displaced people.
Denise Baleye said her younger sister's two children aged four and 21 had been killed in the blasts.
"May the government help us to return to our villages," she implored.
On May 7, the conflict also hit neighbouring South Kivu province when a bombing, blamed on the M23, killed seven people.
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