It is thought that Guede will leave Viterbo's Mammagialla prison on Wednesday morning before returning to his cell on Friday evening.
The decision was made by a probate court in Rome, which overturned an initial decision by a court in Viterbo blocking the 29-year-old's release.
“I will be able to feel the sun on my skin and be able to look out of the window without bars in front of my eyes,” La Repubblica reported Guede as saying after the ruling.
“Thirty-six hours, each one of them precious – I thank everybody who has had faith in me,” he added.
Guede is the only person to have been definitely convicted for Kercher's murder following the conviction, acquittal, re-conviction and eventual definitive acquittal of American Amanda Knox and her former boyfriend, Rafaelle Sollecito.
Guede, who arrived in Italy from the Ivory Coast when he was five, has consistently denied playing any part in the murder and claims to have been a scapegoat.
But Knox, whose case over rights violations she allegedly suffered at the hands of Italian authorities during the investigation into the murder, was last week accepted by the European Court of Human Rights, told La Repubblica: "I'm upset by the fact that Guede has never shown any remorse and hope that whoever granted him permission [to take temporary release] did so only as part of a social reintegration programme."
Guede has already served eight years in jail for the murder and will be eligible for parole in 2018.