Thalang Police led by Capt Kraisorn Boonprasop along with Kusoldharm rescue workers were called to the accident at 5:45am.
At the scene, the pickup truck driver, Sonsitthi Raeden, 43, from Krabi, was unconscious and unresponsive in the cab.
Rescue workers used hydraulic cutters to free him and rushed him to Thalang Hospital, but he was pronounced dead on arrival.
The passenger in the vehicle, Sarawut Prawong, 18, had suffered a back injury and was also taken to Thalang Hospital, said Capt Kraisorn.
“Mr Sarawut said that they were carrying more than four tons of watermelons from Krabi to markets in Patong,” Capt Kraisorn explained.
“It was raining and the road was wet and slippery, and the driver lost control of his vehicle at the monument and hit the barrier,” he added.
Police are still investigating the accident and have yet press any charges, he added.