Macdonald became eligible this month for parole, after he was sentenced to five years' jail for arson, vandalism and killing deer and calves on neighbouring Feilding farms.
His term was imposed in September, after he was found not guilty of murdering his wife's brother Scott Guy by a High Court jury in July.
When he was sentenced, Macdonald had already served more than a year in prison awaiting trial. So, this month he had officially served a third of his sentence and became eligible to go before the board.
It is understood his hearing will take place at Manawatu Prison today.
Mr Guy's wife, Kylee, now a solo mother to their two young boys, will not attend.
She did not want to comment on Macdonald or his bid for freedom.
Mrs Guy is still working with private investigators after launching her own inquiry into her husband's death. He was shot in the driveway of their farm in July 2010.
Police are not looking for anyone else in connection with his death, but did not seek a retrial for Macdonald.
Through a representative Mrs Guy told the Herald she was "not giving up on Scotty".
She encouraged anyone with any information to come forward and contact the investigators.
"Justice needs to be done ... it would mean so much to our family and friends and especially our sons. We can't move forward without closure."
She wanted the public to think hard about anything they knew about Macdonald or her husband's death that could help her get answers.
She said it did not matter how big or small, "it could be what we need".
Macdonald is married to Mr Guy's sister Anna. Since his arrest, the couple have separated but reportedly remain in contact for the sake of their four young children.
Most initial parole applications are declined. The board uses the first hearing to establish contact with the prisoner and to ascertain what rehabilitation is needed before release can be properly considered.
* Can you help? If you have information on Scott Guy's murder, email the private investigators working on the case at info@scottyguy.org.nz, call your local police or Crimestoppers anonymously on 0800 555 111
