The accident happened about 10 am at an intersection along Wiset Road near the Phuket Raumjai Rescue Foundation building.
The man's motorcycle was completely wrecked in the collision. Witnesses said its driver was not wearing a helmet and died instantly from severe head injuries.
Wreckage from the collision remained strewn across one lane of the road while emergency services attended to the accident.
The driver of the truck, which was laden with beer and driving from the direction of Rawai beach, suffered injuries to his legs in the crash, and was taken to Vachira hospital.