To provide an optical element including a surface-emitting type semiconductor laser and an photodetector element, having a desired plurality of dielectric layers, and its manufacturing method. An optical element in accordance with the present invention includes a surface-emitting type semiconductor laser including, above a substrate, a first mirror, an active layer and a second mirror disposed from the side of the substrate, a photodetector element, that is provided above the surface-emitting type semiconductor laser, including a first contact layer, a photoabsorption layer and a second contact layer disposed from the side of the surface-emitting type semiconductor laser, a first dielectric layer formed above the substrate, and a second dielectric layer formed above the surface-emitting type semiconductor laser, wherein the first dielectric layer covers a side surface of a first columnar section including at least a portion of the second mirror, and the second dielectric layer covers a side surface of a second columnar section including at least a portion of the second contact layer.