Firefighters and police are at the scene on Quay Street near Britomart.
A police spokesperson confirmed officers were responding to the incident – reported at 11.40am.
“Police have confirmed one person has died in the Quay St fire,” they said.
“FENZ have extinguished the fire and police have established that one person was in the car at the time of the fire, and this person has died.
“Enquiries are underway to establish the circumstances that led to the fire.
“Quay Street is expected to be blocked for several hours and people are asked to avoid the area.”
Police were on the scene “very quickly” – within minutes – after the car went up in flames, one worker said at a restaurant over the road.
At the scene, police officers were suggesting to parents to take children away.
“It’s probably not a good idea to have a kid anywhere near this,“ one officer said to a parent.
A man who works in the nearby Ferry Building on Quay St said he saw the vehicle on fire just as the first fire engine turned up.
”There was fire coming from the front and rear of the car. The boot of the vehicle was on fire and the bumper and boot area had melted,” said the man, who did not want to be named.
The man said he spoke to two people at either end of the cordon, the length of a whole block along Quay St, who said the police had advised it was a crime scene and the person in the vehicle had died.