The National Prosecuting Authority also says it has been informed by Pistorius' defense lawyers that they will oppose the appeal.
The NPA said today it believes there are "reasonable prospects of a successful appeal based on a question of law."
Prosecutors say Judge Thokozile Masipa may have made an error when she found the double-amputee Olympic runner not guilty of murder for shooting girlfriend Reeva Steenkamp through a toilet cubicle door in his home. Masipa instead convicted Pistorius of a lesser charge of culpable homicide, or manslaughter.