To provide a plate material feeding method and a plate material feeding device of simple mechanism.

This plate material feeding method comprises a process for raising a tray 13 loaded with a plurality boat-shaped barrel plates 14, which are aligned in the rising posture, to a certain height, a process for tilting the tray 13 at a certain angle from the horizontal state, and a process for holding the predetermined number of boat-shaped barrel plates 14 placed on the tray, of which height and tilting state are maintained, while maintaining the tilting angle and for transferring the boat-shaped barrel plates 14 onto a tilted base 61 of a stock section 60 tilted at the same angle, while maintaining the tilting angle thereof.