The present invention proposes a gate driver including a plurality of gate driver on array (GOA) units. Each of the GOA unit includes a main driving circuit, a starting signal output circuit, and a plurality of gate driving circuits. The gate driver utilizes a starting signal and two inversed clock signals to control the charging period and the discharging period of the gate driver. Furthermore, the gate driver utilizes multiple clock signals to control the output of the gate driving signals. In this way, the number of the clock signals is reduced and thus the power consumption is also reduced.