A Garda spokesman said there would be no immediate charges, as a file was being prepared for the DPP.
The woman had been detained at Enniscorthy Garda Station since Sunday night in connection with the death of Walter Plunkett, of Ballyrea, Ballyedmond, Gorey, Co Wexford, on Sunday afternoon.
She was known to the 84-year-old victim.
Mr Plunkett was found by gardaí in the front garden of his home where he was pronounced dead.
His autopsy revealed that he died of asphyxiation.
He had been living in Ballyedmond for the past 20 years, having moved back to Ireland from Middlesex in England, where he had worked as a chef.
Mr Plunkett will be laid to rest alongside his wife Elizabeth in Monamolin Cemetery on Friday.
Mr Plunkett’s daughter Cathy Bottomley identified her father’s body at Waterford Regional Hospital late Monday evening.
She said: “My father was well-liked by all his neighbours and friends in Ballyedmond.”