The man was taken to hospital in a critical condition but died four days later. Police have not yet released his name.
A Dargaville man died 26 days after a crash on State Highway 12 near Turiwiri, Dargaville.
William Harold Ball was the front seat passenger in a vehicle that left the road and went into a ditch.
He was wearing a seatbelt but it is suspected his head struck the windscreen. He was taken to Whangarei Hospital but his condition deteriorated.
Ewers said police were still piecing together all the evidence to establish what may have caused the crash.
He was concerned last year's horror road toll in which 40 people died in accidents on the region's roads would be exceeded this year after the bad start to the year.
Ewers earlier said one of the most frustrating things about the road toll was most deaths could be prevented if motorists stuck to basic safety rules.
"The messages are the same as last year and the years before that, watch your speed, drive to the conditions, wear your seat belts and don't drink and drive," he said.