The present invention discloses a method and a device for forming a curved plate glass, in which a plate glass is softened so as to form the same into a three-dimensional shape. The forming device of the present invention comprises: a mold set; a conveyor; and a continuous furnace. The mold set includes a lower mold having a cavity for supporting the periphery of the edge of a plate glass and accommodating the plate glass, and an upper mold for forming the plate glass into a curved plate glass by mold-closure with the lower mold. The conveyor is provided to transfer the mold set from a loading station for loading a plate glass to the mold set to an unloading station for unloading the curved plate glass from the mold set. The continuous furnace is provided between the loading station and the unloading station. In the continuous furnace: a preheating zone, in which the plate glass is preheated from the loading station towards the unloading station; a pre-fitting zone, in which the upper mold presses the plate glass by its own weight and softens the plate glass so as to be pre-fitted to the lower mold, thereby preforming the plate glass into a curved plate glass preform; a pressing zone, in which the curved plate glass preform is pressed by the upper mold so as to be precisely formed into a curved plate glass; a slow cooling zone, in which the curved plate glass is slowly cooled; and a cooling zone, in which the curved plate glass is cooled, are continuously arranged. According to the present invention, the curved plate glass having a three-dimensional shape can be precisely manufactured by the preheating, preforming, precise forming, slow cooling, and cooling of the plate glass, and defects can be prevented so as to enable a productivity to be improved.