Kathu Police were notified of the accident at about 5am.
Police along with rescue workers from Kathu Municipality and the Kusoldharm Foundation arrived at the scene to find the body of Suttisak Ketkhao, 33, from Huai Yot District in Trang, on the road. He had suffered a fatal head injury.
About 50 metres away was his Trang-registered Honda Wave motorbike in the middle of the road.
According to the initial police investigation, Mr Suttisak was riding from the Si Kor Intersection towards Kathu Municipality at high speed. He lost control of the motorbike and overshot the curve in front of Wat Kathu. His head hit the road in the fall. Police and rescue workers made no mention of any helmet found at the scene.
His body was taken to Vachira Phuket Hospital, while officers took the motorbike back to Kathu Police Station as evidence to complete their investigation.
According to national road safety agency ThaiRSC, so far 19 people have died and 2,380 people have been injured in road accidents in Phuket since the beginning of the year.