A method of manufacturing containers of paper material for foodstuffs, in particular pastries, wherein the container comprises a single sheet portion of flexible paper material defining a flat bottom wall and a side wall emerging from the bottom wall. The container has a side wall comprising, in section, at least one curvilinear stretch (10) for defining a rounded or convex conformation of the side wall. The method contemplates a first step for making the bottom wall (2) provided with an upper surface (2a) and a lower surface (2b), and a side wall (3) emerging from the bottom wall (2) in such a manner that in cooperation with said bottom wall it defines a holding region (21) whose bottom consists of said lower surface (2b), and a second step of overturning the side wall on the opposite side relative to the bottom wall (2) for defining a cavity (7) having an upwards facing opening in the normal use position of the container.