Police said the accident happened at 2am on Chiang Rak-Bang Khan road in Tambon Klong Nueng of Pathum Thani’s Klong Luang district.
The motorcyclist was identified as Dolchai Pongwattana, 22.
Truck driver Panya Harnna, 36, said he was returning home after delivering goods when he felt sleepy. He parked at the side of the road to get some sleep and was awoken by the sound of the crash.