A single tooth is all that remains of the young nationalist who was murdered in January 1961 at the age of 35, just months after becoming Congo's first post-colonial prime minister.
A coffin containing the remains was to be enshrined in a mausoleum in Kinshasa, in a ceremony hosted by President Felix Tshisekedi coinciding with the country's 62nd anniversary.
Topped by a large statue of Lumumba, the mausoleum is located on a main avenue of the capital which also bears his name.
Lumumba was among the vanguard of pan-African leaders who led the charge to end colonialism in the late 1950s.
He rose to prominence in 1958 when he launched a political party, the Congolese National Movement (MNC), which called for independence and a secular Congolese state.
His party won national elections in May 1960, a month before independence from Belgium, leading him to be named first prime minister of the country when it became independent.
He stunned Belgium with a speech on independence day -- attended by King Baudouin -- that accused the exiting colonial masters of racism and "humiliating slavery" of the Congolese people.
Within three months, Lumumba was forced out by a coup fomented with the help of Belgium and the CIA, which also opposed the support he had requested from the Soviet Union.
In January 1961, Lumumba was handed over to the authorities in mineral-rich southeast Katanga province, which had seceded from the fledgling nation months earlier with Belgium's support.
He was shot dead and his body was dissolved in acid, but a Belgian police officer involved in the killing kept one of his teeth as a trophy.
After years of campaigning by his family, Belgium returned the tooth on June 20, a move that followed a visit of reconciliation by Baudouin's nephew and successor, King Philippe.
The remains were taken to Lumumba's home area of Sankuru in the centre of the country, to his political stronghold of Kisangani in the northeast and finally to the place where he was murdered before being flown to Kinshasa.
Five former prime ministers joined a funeral vigil on Thursday alongside current government chief Jean-Michel Sama Lukonde.
"The figure of Patrice Lumumba is a prime symbol of national unity, transcending political differences," said Evariste Mabi, a premier in the 1980s under Lumumba's nemesis, dictator Mobutu Sese Seko.
"(He) embodies the people's successful struggle for freedom."