The driveway entrance to the Wyndham St property has been cordoned off with emergency services tape and a female police officer was guarding the two-storey home. There was also one other undercover police vehicle parked outside.
Police could not make any comment at the scene.
Manawatu Fire Service area commander Mitchell Brown said an investigation of the fire-damaged home had found no smoke alarms installed in the property.
"Smoke alarms are your only voice in a house fire. You're on a hiding to nothing if you're in a house fire and you don't have any smoke alarms," said Brown.
Mr Mitchell said the dead man was sleeping on the upper storey of the house which had become smoke-logged.
He made a fresh appeal for people to install working smoke alarms throughout homes to avoid a repeat of today's tragedy. It was important to position them near sleeping areas and on both levels of two-storey homes.
Early investigations revealed the fire had started on the ground floor in the stairwell adjacent to a woodburner. It had travelled up the stairs to the second storey destroying a key internal escape route.
A Fire Service spokeswoman said firefighters were called to a property in Wyndham St after reports of smoke in the area.
At its height four fire crews from Ashhurst and Palmerston North attended the fire.
A police spokeswoman said emergency services were called to the blaze and found the only person residing at the property had died.
Police and fire investigators would now look at the circumstances around the cause of the fire and the death.
Meanwhile, investigations will continue into the cause of a suspicious fire in Whanganui last night which destroyed two homes.