PURPOSE: A liquid crystal display and a driving method thereof are provided to reduce light leakage while increasing the driving voltage of a liquid crystal display unit. CONSTITUTION: In a liquid crystal display and a driving method thereof, first and second substrates are opposite to each other. A liquid crystal layer is interposed between the first and second substrates and includes a liquid crystal module. A gate line is arranged on the first substrate transmits a gate signal. A first data line is arranged on the first substrate transmits a data voltage . A first power line is arranged on the first substrate and transmits a first voltage and second voltage alternately. A first switching unit is connected to a gate line and the first data line. A second switching unit is connected to the gate line and a first power line. A first pixel electrode is connected to the first switching unit. A second pixel electrode is connected to the second switching unit.
