A transflective liquid crystal display panel having a single gap is provided. The liquid crystal display panel has a first substrate, a second substrate substantially corresponding to the first substrate, and a liquid crystal layer disposed therebetween. The first substrate includes a plurality of pixel regions, and each pixel region has at least one reflection region covered with a reflective electrode and at least one transmission region. When voltage is not applied, the liquid crystal layer in the transmission regions and in the reflection regions has a phase difference of half wavelength, and when a voltage is applied, the liquid crystal layer in the transmission regions has no phase difference, and the liquid crystal layer in the reflection regions has a phase difference of quarter wavelength.