A liquid crystal display device includes a first substrate, wherein a pixel region is defined by a gate line and a data line, the pixel region is divided into a reflection region and a transmission region, an electric field guide window is formed on the transmission region, a pixel electrode is formed on the pixel region, and a predetermined step difference part is formed on a boundary between the reflection region and the transmission region, a second substrate facing the first substrate and having a dielectric rib spaced apart by a predetermined distance from the electric field guide window, and a liquid crystal layer interposed between the first and the second substrates.