To provide a manufacturing method which makes it possible to obtain an optical element having an optical function surface of good surface quality by press forming the optical function surfaces to the surface roughness approximate to the surface roughness of finished goods, then subjecting the optical function surface to an improvement of the surface roughness without collapsing the shape formed by extrusion forming.

The manufacturing method of obtaining the finished optical element 101c having the desired optical function surface by thermally softening a preform 101c which is an optical element blank and press forming the blank to obtain the formed optical element 101b, then subjecting the formed optical element 101b to surface removal processing has a process of press of forming the optical element to the formed optical element 101b of which the optical function surface has the surface roughness approximate to the surface roughness of the finished goods from the preform 101c and a process of obtaining the finished optical element 101c by subjecting the optical function surface of the formed optical element 101b subjected to the press forming to the surface removal processing.