The enhancement-mode gallium nitride (GaN) high-electron-mobility transistor (HEMT) offers faster switching speed but introduces large dv/dt, which causes crosstalk issues and further raises the risk of false turn-on. Traditional gate drivers address this by increasing the gate resistance to reduce switching speed, but this approach also elevates switching loss, especially at high temperature because GaN HEMT’s transconductance decreases with increase of temperature. To mitigate this issue, this paper proposes a driver circuit featuring adaptive gate resistance under different temperatures. By incorporating a negative temperature coefficient (NTC) resistor, the gate resistance decreases as temperature rises. As a result, GaN devices can switch faster at high temperature, thereby reducing switching losses. Compared with the traditional driver circuit, the proposed method improves the switching speed by 31% through the adaptive gate resistance and maintains the same maximum crosstalk voltage peak under a wide temperature range.