“One person was in the house at the time of the fire and was found unresponsive by emergency services,” the spokesperson said.
A Fire and Emergency New Zealand spokesperson said it took four crews to put out the “well-involved” blaze.
Hokitika Chief Fire Officer Peter Cuff said shortly after arrival firefighters were made aware there was a person unaccounted for.
“The brigade members searched and found that person and managed to get them out of the house,” Cuff said.
“The firefighters then commenced resuscitation efforts, but it was unfortunately unsuccessful.
“There is extended family of the deceased on-site now, I have no doubt they will be feeling the effects of what has happened.”
Thirty-five firefighters worked on the scene. An ambulance was also in attendance.
The police spokesperson said the fire is being treated as unexplained.
“A scene guard was in place overnight and further inquiries will be undertaken today to determine the cause of the fire.”
This is the second fatal housefire in the South Island in the past two weeks - following a blaze in a Manapōuri home which claimed the life of a mother and her 11-year-old son.
Meanwhile, at 12.40am, firefighters were also called to a house fire in the Waihopai Valley area of Marlborough.
A Fenz spokesperson said there was a small fire in the house, but crews had difficulty accessing it.
No one was inside.