Emergency services were called to the incident at the Bush Inn Centre, Upper Riccarton, at 2.40pm.
The victim, a 57-year-old man who was a self-employed tradesman, was clearing gutters around the centre when he was fatally struck by an SUV, Superintendent Lane Todd said.
He had just celebrated his birthday four days earlier.
Todd said an investigation is under way, but it appears it was an accident at this stage.
"Obviously a very tragic incident for all those concerned.
"The driver's obviously very tragically taken it quite badly, as you'd expect, so we're just working with the driver as well," he said.
"Condolences go with the family concerned. We're working that through with the wider family at the moment and it's obviously been a tragic incident for them as well, but also the employer and the person's work colleagues and the environment will be tragically affected so sympathies go with them."
A witness at the scene said the man was freed by Fire and Emergency NZ personnel and then covered with a blanket.
A St John spokesman referred all inquiries to police.
The area around the incident was cordoned off.
-Additional reporting NZ Herald
