The Paralympic gold medallist was released on parole in October after serving a fifth of his five-year prison term for the "culpable homicide" of Steenkamp, whom he killed by firing four shots through a locked toilet door on Valentine's Day 2013.
Prosecutors said Pistorius, 29, should be convicted of murder and sent back to jail because he knew the person behind the door could be killed when he fired. A murder conviction would result in a minimum sentence of 15 years in prison.
"The judgement will be delivered at 09:45 (0745 GMT) on 3 December 2015 at the Supreme Court of Appeal," the court said in a statement on Tuesday.
Pistorius, whose lower legs were amputated when he was a baby, denied during his six-month trial that he deliberately killed Steenkamp, saying he mistook her for an intruder at his home.
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High Court Judge Thokozile Masipa ruled last year that the state had failed to prove Pistorius had shown "intent" or "dolus eventualis", a legal concept that centres on a person being held responsible for the foreseeable consequences of their actions.
The state argued at the appeal that Masipa misinterpreted some parts of the law, including "dolus eventualis".
If the court of appeal overturns Masipa's verdict, she will be responsible for passing a new sentence on Pistorius, according to legal experts.
(Reporting by Joe Brock; Editing by James Macharia and Mark Trevelyan)
