An optical modulator unit, an optical modulator, and a method of fabricating are provided. The optical modulator unit includes a first contact layer transmitting infrared rays, a lower reflection layer disposed on the first contact layer, an active layer, including a multiple quantum well, disposed on the lower reflection layer, and an upper reflection layer disposed on the active layer. The optical modulator includes a plurality of optical modulator units sharing the first contact layer. The method includes sequentially stacking a first contact layer, a lower reflection layer, an active layer, an upper reflection layer, and a second contact layer on a substrate; etching the second contact layer, the upper reflection layer, the active layer, and the lower reflection layer, exposing a surface of the first contact layer; forming a first electrode on the first contact layer; and forming a second electrode on the second contact layer.