Michael Waipouri was found guilty of the murder and kidnapping of Waiuku man Lance Murphy last Wednesday 1 March.
The jury deliberated for two hours before returning with the guilty verdict.
Mr Murphy’s body was found in a ditch near Wellsford in December 2015 after he had been recorded as missing for nearly three weeks.
Waipouri bludgeoned Mr Murphy with a baseball bat, before using a branch.
During the trial, Mr Waipouri’s claims of acting in self-defence were dismissed by the judge, Justice Hinton.
Also on trial was Steve Gunbie, who was found not guilty on kidnapping and accessory to murder charges.
Mr Waipouri will be sentenced in April.