Passing the judgement, Judge Masipa said Pistorius is "a good candidate for rehabilitation and the other purposes of punishment need not play a dominant role...".
The judge continued to say that she would be ready to hear any appeal if that state would like to appeal her decision.
Given the time Pistorius has already served, he could be out of prison in three years time.
Oscar Pistorius had his original conviction of a manslaughter upgraded to murder on appeal. The former paralypiam has already served 12 months of a five-year prison sentence for manslaughter and is currently under house arrest.
The former athlete was taken to prison immediately following his six-year sentence for murder. He will be serving the sentence in the hospital wing of the Kgosi Mampuru II prison in Pretoria, where he served part of his original sentence.
After the judge delivered her verdict, parents of Reeva deceased girlfriend June and Barry had no immediate reaction but their lawyer indicated the result was "fair".
Pistorius, who claimed he thought Ms Reeva Steenkamp was an intruder when he shot her dead at his home in 2013, was originally sentenced to five years in prison in October 2014 and subsequently released on house arrest 12 months later.