Detective Senior Sergeant Paul Wilson said officers were called about 3pm on Thursday to a house in the township of Pukehina where a woman had died.
Early today, police were called back to the Old Coach Rd property, where a man was found dead in a separate house.
On Thursday, a 50-year-old man was arrested and charged in relation to the woman's death.
He was taken into custody and was due to appear in Tauranga District Court today, charged with assault on a person in a family relationship.
Meanwhile, the death of the man found today is being treated as unexplained.
Wilson said scene examinations were being conducted. He said police were not ruling out further arrests or charges.
Post-mortems for both the woman and the man would take place.
"Police would like to speak with anyone who has information about what has happened, or who may have visited the Old Coach Road address between 7pm Wednesday 31 December 2025 and 3am Friday 2 January 2026.
"If you can help, please make a report through 105, either online or over the phone, and reference file number: 260101/9901."
