Members of the public tried to help save the man yesterday afternoon.
Police are appealing for witnesses following a road crash in Kidlington.
A black and green Kawasaki motorbike struck the crash barrier on the Oxford bound carriageway of the A4260 Frieze Way, shortly after 5pm yesterday.
Members of the public, paramedics and Thames Valley Air Ambulance crews provided the 31-year-old man with first aid but despite their best efforts, he sadly died at the scene.
His next of kin have been informed and are being supported by a specially trained Family Liaison Officer.
Investigating officer PC Dean O’Dell of the Joint Operations Roads Policing Unit said: “First and foremost, my thoughts and the thoughts of Thames Valley Police are with the family and friends of the man who has died as a result of this collision.
“They are receiving support at this very difficult time.
“I would like to thank those members of the public who stopped at the scene to try and help the motorcyclist, providing immediate first aid for him.
“This collision took place in the early evening and I would anticipate a number of people will have been driving in the area at the time.
“I am appealing to anybody who witnessed the collision, or who may have dash-cam footage that may assist this investigation to please get in touch with Thames Valley Police, either by making a report online or by calling 101, quoting reference number 43220292035"