To provide a method for manufacturing an uneven thickness resin sheet capable of collectively anneal treating a plurality of uneven thickness resin sheets and suppressing the deformation of the uneven thickness resin sheet, and a stacking method.

The uneven thickness resin sheet S is anneal treated by an annealing treating device 60 after being stacked in layers in the thickness direction by a stacking device 34. The stacking device 34 stores the resin sheet S in an internal part of a pallet 40 to stack the pallet 40.