According to one embodiment, a stacked film including at least a silicon oxide film is formed by stacking a plurality of films formed of different materials and a hard mask pattern is formed on the stacked film. Then, a stacked film pattern of a predetermined shape is formed by performing anisotropic etching on the stacked film by using the hard mask pattern as an etching mask and the hard mask pattern is removed. The hard mask pattern is formed by stacking at least one first hard mask layer and at least one second hard mask layer. The first hard mask layer is formed of a material having a higher removability in wet etching than the second hard mask layer. The first hard mask layer is arranged immediately above the stacked film.