The ute was stopped in its tracks in Lower Shotover Rd, about 12.30pm, and was broken in half by the 20m tree.
Skid marks were left on the road.
Queenstown police, a St John Wakatipu ambulance and Arrowtown and Frankton firefighters attended.
A temporary police roadblock was set up between the Lower Shotover and Domain Rds corner and the junction of Lower Shotover and Speargrass Flat Rds.
Sergeant Steve Watt, of Queenstown, said the man was travelling towards State Highway 6.
The damage to the ute was "extensive".
"Witness accounts from vehicles travelling behind suggest they saw the tree coming down, as did the driver of the ute.
"He applied the brakes and obviously the tree has fallen on top of the cab."
Sgt Watt said a "qualified individual" would make an assessment of the tree.
He said yesterday it was the early stage of a long investigation and a serious crash investigator was on the way.
Queenstown Lakes District Council spokeswoman Meaghan Miller said the council was shocked by the accident.
It was not clear yesterday if the fallen tree stood on private land or road reserve.
"The council will undertake to have a survey done and either way the remainder of the trees in the row will need to be inspected by an arborist to ensure no further members of the community are endangered.
"The trees were not planted by the council."
