Anyone who witnessed the crash or has information should contact Detective Alex Simister by phoning 105, or anonymously through Crimestoppers on 0800 555 111.
A police spokesperson said the crash occurred when two Hawke's Bay men were travelling back from a day at the beach.
The driver appeared to have lost control of the ute, which rolled and landed in a paddock, the spokesperson said.
"The passenger took the brunt of the impact and has died as a result."
The vehicle is being examined and the Serious Crash Unit is investigating. Police are speaking to the driver and are not looking for anyone else.
There were two occupants in the vehicle, and three ambulances are believed to have attended.
