A touch display device at least including a gate driver is provided. The gate driver at least includes a pull-up control circuit, a pull-down control circuit and a pull-up output circuit. The pull-up control circuit sets the voltage level of a first node to a first voltage level. The pull-down control circuit is configured to set the voltage level of the first node to a second voltage level and includes a first transistor receiving an operation voltage. The second voltage level is lower than the first voltage level. The pull-up output circuit generates a scan signal according to the voltage level of the first node. During a first display period and a second display period, the operation voltage is equal to a first gate voltage. During a touch-sensing period, the operation voltage is equal to a second gate voltage that is lower than the first gate voltage.