A scan driver includes a voltage setting circuit, a counter circuit, a logic circuit, a dynamic decoder, N level shift circuits and N output stage circuits, wherein N is a natural number. The voltage setting circuit sets N voltage signals to a first level. The counter circuit provides count data to the logic circuit, which generates M control signals according to the count data, wherein M is a natural number. The dynamic decoder includes multiple transistors, arranged in N rows, for receiving the respective N voltage signals. The transistors are further arranged in M columns and are controlled by the respective M control signals to determine levels of the N voltage signals. The N level shift circuits lift the levels of the respective N voltage signals, and the N output stage circuits output respective N gate signals based on the N voltage signals whose levels are shifted.