The 16-year-old rider of a Kawasaki KXF motorcycle was driving eastbound on Burnett Street in Bundaberg South, when he hit the side of a Mitsubishi Triton Ute, near Hunter Street, at 2.30pm on Friday.
The teenager suffered life-threatening injuries and was transported to Bundaberg Hospital for treatment.
The driver of the ute, a 63-year-old man, was not injured.
The forensic crash unit is investigating the circumstances around the crash.
Anyone with dashcam footage is urged to contact the authorities.