The body of the man, who appeared to be 30 to 40 years old, was found in the middle of the Ban Chang-bound road at about 4am at kilometre marker 16 in Moo 8 village in tambon Samnakthon.
He suffered head injuries and there was evidence his body had been dragged along the road.
A plastic bag with Bt200 in it was found on his body.
He was not carrying an identification card.
Police also found small pieces of a vehicle’s bumper bar at the scene.
Police will check security cameras in the area.