To provide a vehicle load carrying platform for plate material transportation capable of easily and stably positioning a plate material carrier on a floor surface.

This vehicle load carrying platform for plate material transportation has the plate material carrier and the floor surface 2, and the plate material carrier has a lower member 4a on which a lower end part of a plate material 23 is placed and an erecting member 4b extending upward from the lower member 4a and against which the plate material 23 is set. A wheel 7 and a position regulating device 6 to position and regulate the wheel 7 vertically against the lower member 4a are provided on both end parts of the lower member 4a. The floor surface 2 has a pair of rails 2b to guide and support the wheel 7. The rails 2b have a recessed part 2b1 recessed and provided from a main floor part 2a of the floor surface 2 and a rail engaging part 2b2 provided on a bottom surface of the recessed part 2b1 and with which a wheel engaging part 7a formed on an outer peripheral surface of the wheel 7 is engaged. The lower member 4a is changed over to a position where it is lifted from the main floor part 2a and to a position where it is set on the main floor part 2a by positioning and regulating the wheel 7 vertically by the position regulating device 6.