A 19-year-old bike rider was travelling alongside Brighton Highway, Elwood, simply after 11pm when his bike collided with a pedestrian.
The 32-year-old pedestrian was taken to hospital with life-threatening accidents.
He died on the hospital.
The rider additionally suffered critical accidents and was taken to hospital.
An investigation into the circumstances of the accident is underway.
Anybody who noticed the collision or has dashcam footage is urged to name Crime Stoppers on 1800 333 000.