To provide an easy-to-make, inexpensive sheet tray, which is convenient for preparing, weighing, or transferring a solid material aggregate, such as powder, grains, massive materials, or the like, and can be stacked stably.

The edge of the edge-folded type sheet tray is folded outward linearly or curvedly to have a relatively large width in a sloped direction to form circular grooves of curved shape. Each circular groove holds a unit amount of a solid material to be transferred temporarily in such a way that powder is hard to remain while grains or tablets are hard to roll out. The tray can be stacked stably, with the solid material prepared on the flat bottom of the tray, and made easily and inexpensively.