A new and improved optical element manufacturing method, through which lens elements can be efficiently mounted on a silicon V-shaped groove substrate at lower manufacturing costs, is provided. The method comprises a lens element forming step in which an oxide layer 104 is formed at a supporting layer 102 and lens elements 120 are formed at the upper surface of the silicon oxide film, a coating step in which a solder connection metal film is coated onto the side surfaces of the lens elements and a separating step in which the lens elements are separated by removing the silicon oxide film. Through this method, the solder connection metal film can be formed with ease at the sidewalls of the lens elements. The lens elements with the solder connection metal film formed at the side walls thereof can easily be soldered onto a supporting substrate.