The present disclosure relates to a polarization converting device and a method for manufacturing the same, wherein the polarization converting device includes a polarization separation unit aligned with a plurality of unit blocks including an optical separator transmitting a first polarization between an upper surface and a lower surface and reflecting a second polarization, and a phase retarder aligned in correspondence to an upper surface of each unit block of the polarization separation unit where a first region and a second region are alternately formed, wherein any one of the first and second regions of the phase retarder converts the polarized light while the other region emits the polarized light as it is.