The man was arrested this morning and is being held at Mallow Garda station.
The incident unfolded after 4pm on Christmas Day when an argument broke out at a house in Glen North Banteer.
The injured woman was at home with her son and daughter in law and another man on the day in question.
The 51 year old woman left the house during the argument and was stabbed in the upper body.
Emergency services rushed to the scene and the woman was taken to CUH where she underwent surgery for the stab wounds and is now in a stable condition.
Members of the Garda Armed Support Unit subsequently discovered an injured man close to the house and he was also taken to CUH where he was treated for non-life threatening injuries.
Investigations into the incident are ongoing.
